text:
What is the longest known stalemate your opponent in x-moves problem?
What is the longest known stalemate your opponent in x-moves problem where the given stalemate is the fastest one from the initial position? A win is not possible, but stalemating your opponent so they can't move is, and any other draw takes at least as many moves.
The solution does not have to be unique. The stalemating side will try to keep the game as short as possible, while the to-be-stalemated attempts to prolong it.
Here is an example of such a "stalemate your opponent" problem that is in 2 moves long.
[FEN "5k1K/8/7P/8/8/7b/8/8 b - - 0 1"]
[startflipped ""]

1... Bf5 2. h7 Kf7.

Another example is this with White to move. It is the record for White having only a king.
[Title "CJ Morse, The Problemist 1985"]
[FEN "8/ppp1p3/4p3/4p3/8/8/1pp5/brk1K3 w - - 0 1"]

1. Ke2 e4 2. Ke1 e3 3. Ke2 e5 4. Ke1 e2 5. Kxe2 e4 6. Ke1 e3 7. Ke2 e6 8. Ke1 e2 9. Kxe2 e5 10. Ke1 e4 11. Ke2 e3 12. Ke1 e2 13. Kxe2 c6 14. Ke1 c5 15. Ke2 c4 16. Ke1 c3 17. Ke2 b6 18. Ke1 b5 19. Ke2 b4 20. Ke1 b3 21. Ke2 a6 22. Ke1 a5 23. Ke2 a4 24. Ke1 a3 25. Ke2 a2 26. Ke1

Can anyone find a longer fastest stalemate your opponent in x-moves problem than the 35-move one below that I created?

Do you require the solution to be unique?  Would your first diagram be acceptable (albeit much too short to be a record) if Black still had all the other stalemating moves but not the Bxh7 draw?

No it doesn't have to be a unique solution.

That's what I guessed though "all other moves would lose" suggests you didn't even allow alternative stalemating moves.

Yes I didn't consider the possibility of other draws or even stalemates of equal length.  They can be allowed.  I believe the constraints I'm looking for are 1. The position forces Stalemate 2. The stalemating side has no winning strategy available and 3. There are no faster draws

It is also assumed the opponent will not play moves that lose or draw faster.

Or even get stalemated faster?  The example you give gives black a choice between 5 move counts depending on how many of the a-, b-, c-, and e-pawns start with a double move.

Yes avoiding faster stalemates is also part of the problem's assumption. The opponent will try to prolong the draw as long as possible.

Took me a while to realize that the first board was flipped.

The following thirty five move position is the longest position I could create.
White basically checks with four knights on c2 before blocking the black pawns with the king and knight on h1 while keeping the black king boxed in on a1. I tried extending this by adding another white knight on a3 to check on c2 but a black queen or black bishop cannot be added to capture on c2 since black still has eight pawns and there would be no square to place a black knight on to capture on c2.
[FEN "8/p1p2p1p/5pbp/8/qN1N4/4N2p/pr1r4/k1K1N2N w - - 0 1"]

  1. Nbc2 Bc2 2. N4c2 Rbc2 3. N3c2 Rc2 4. Nc2 Qc2 5. Kc2 h2 6. Nf2 h5 7. Nh1 h4 8. Nf2 h3 9. Nh1 h6 10. Nf2 h5 11. Nh1 h4 12. Nf2 f5 13. Nh1 f4 14. Nf2 f3 15. Nh1 f6 16. Nf2 f5 17. Nh1 f4 18. Nf2 a6 19. Nh1 a5 20. Nf2 a4 21. Nh1 a3 22. Nf2 c6 23. Nh1 c5 24. Nf2 c4 25. Nh1 c3 26. Nf2 h1=Q 27. Nh1 h2 28. Nf2 h3 29. Nh1 f2 30. Nf2 f3 31. Nh1 f2 32. Nf2 h1=Q 33. Nh1 h2 34. Nf2 h1=Q 35. Nh1

I can't speak to whether this satisfies the (rather awkward) constraints you've put upon the problem, but the longest I was able to find with a rather cursory search was 201 moves:
[FEN "6K1/pn5n/2p3Q1/P1P5/Bp5p/p5p1/pbP3pr/rk5b w - - 0 1"]

1. c4+ Kc1 2. Qh6+ Kb1 3. Qxh7+ Kc1 4. Qh6+ Kb1 5. Qg6+ Kc1 6. Qg5+ Kb1 7. Qf5+ Kc1 8. Qf4+ Kb1 9. Qe4+ Kc1 10. Qe3+ Kb1 11. Qe1+ Bc1 12. Qxb4+ Bb2 13. Qe1+ Bc1 14. Qe4+ Kb2 15. Qe5+ Kb1 16. Qf5+ Kb2 17. Qf6+ Kb1 18. Qg6+ Kb2 19. Qg7+ Kb1 20. Qxb7+ Bb2 21. Qh7+ Kc1 22. Qh6+ Kb1 23. Qg6+ Kc1 24. Qg5+ Kb1 25. Qf5+ Kc1 26. Qf4+ Kb1 27. Qe4+ Kc1 28. Qe3+ Kb1 29. Qg1+ Bc1 30. a6 Kb2 31. Qd4+ Kb1 32. Qe4+ Kb2 33. Qe5+ Kb1 34. Qf5+ Kb2 35. Qf6+ Kb1 36. Qg6+ Kb2 37. Qg7+ Kb1 38. Qb7+ Bb2 39. Qh7+ Kc1 40. Qh6+ Kb1 41. Qg6+ Kc1 42. Qg5+ Kb1 43. Qf5+ Kc1 44.Qf4+ Kb1 45. Qe4+ Kc1 46. Qe3+ Kb1 47. Qg1+ Bc1 48. Kf8 Kb2 49. Qd4+ Kb1 50. Qe4+ Kb2 51. Qe5+ Kb1 52. Qf5+ Kb2 53. Qf6+ Kb1 54. Qg6+ Kb2 55. Qg7+ Kb1 56. Qb7+ Bb2 57. Qh7+ Kc1 58. Qh6+ Kb1 59. Qg6+ Kc1 60. Qg5+ Kb1 61. Qf5+ Kc1 62. Qf4+ Kb1 63. Qe4+ Kc1 64. Qe3+ Kb1 65. Qg1+ Bc1 66. Ke8 Kb2 67. Qd4+ Kb1 68. Qe4+ Kb2 69. Qe5+ Kb1 70. Qf5+ Kb2 71. Qf6+ Kb1 72. Qg6+ Kb2 73. Qg7+ Kb1 74. Qb7+ Bb2 75. Qh7+ Kc1 76. Qh6+ Kb1 77. Qg6+ Kc1 78. Qg5+ Kb1 79. Qf5+ Kc1 80. Qf4+ Kb1 81. Qe4+ Kc1 82. Qe3+ Kb1 83. Qg1+ Bc1 84. Kd8 Kb2 85. Qd4+ Kb1 86. Qe4+ Kb2 87. Qe5+ Kb1 88. Qf5+ Kb2 89. Qf6+ Kb1 90. Qg6+ Kb2 91. Qg7+ Kb1 92. Qb7+ Bb2 93. Qh7+ Kc1 94. Qh6+ Kb1 95. Qg6+ Kc1 96. Qg5+ Kb1 97. Qf5+ Kc1 98. Qf4+ Kb1 99. Qe4+ Kc1 100. Qe3+ Kb1101. Qg1+ Bc1 102. Kc8 Kb2 103. Qd4+ Kb1 104. Qe4+ Kb2 105. Qe5+ Kb1 106. Qf5+ Kb2 107. Qf6+ Kb1 108. Qg6+ Kb2 109. Qg7+ Kb1 110. Qb7+ Bb2 111. Qh7+ Kc1 112.Qh6+ Kb1 113. Qg6+ Kc1 114. Qg5+ Kb1 115. Qf5+ Kc1 116. Qf4+ Kb1 117. Qe4+ Kc1 118. Qe3+ Kb1 119. Qg1+ Bc1 120. Kb8 Kb2 121. Qd4+ Kb1 122. Qe4+ Kb2 123. Qe5+ Kb1 124. Qf5+ Kb2 125. Qf6+ Kb1 126. Qg6+ Kb2 127. Qg7+ Kb1 128. Qb7+ Bb2 129.Qh7+ Kc1 130. Qh6+ Kb1 131. Qg6+ Kc1 132. Qg5+ Kb1 133. Qf5+ Kc1 134. Qf4+ Kb1 135. Qe4+ Kc1 136. Qe3+ Kb1 137. Qg1+ Bc1 138. Kxa7 Kb2 139. Qd4+ Kb1 140. Qe4+ Kb2 141. Qe5+ Kb1 142. Qf5+ Kb2 143. Qf6+ Kb1 144. Qg6+ Kb2 145. Qg7+ Kb1146. Qb7+ Bb2 147. Qh7+ Kc1 148. Qh6+ Kb1 149. Qg6+ Kc1 150. Qg5+ Kb1 151. Qf5+ Kc1 152. Qf4+ Kb1 153. Qe4+ Kc1 154. Qe3+ Kb1 155. Qg1+ Bc1 156. Kb8 Kb2 157. Qd4+ Kb1 158. Qe4+ Kb2 159. Qe5+ Kb1 160. Qf5+ Kb2 161. Qf6+ Kb1 162. Qg6+ Kb2 163. Qg7+ Kb1 164. Qb7+ Bb2 165. Qh7+ Kc1 166. Qh6+ Kb1 167. Qg6+ Kc1 168. Qg5+ Kb1 169. Qf5+ Kc1 170. Qf4+ Kb1 171. Qe4+ Kc1 172. Qe3+ Kb1 173. Qg1+ Bc1 174. a7 Kb2 175. Qd4+ Kb1 176. Qe4+ Kb2 177. Qe5+ Kb1 178. Qf5+ Kb2 179. Qf6+ Kb1 180. Qg6+ Kb2 181. Qg7+ Kb1 182. Qb7+ Bb2 183. Qh7+ Kc1 184. Qh6+ Kb1 185. Qg6+ Kc1 186. Qg5+ Kb1 187. Qf5+ Kc1 188. Qf4+ Kb1 189. Qe4+ Kc1 190. Qe3+ Kb1 191. Qg1+ Bc1 192. a8=Q Kb2 193. Qd4+ Kb1 194. Qb7+ Bb2 195. Qh7+ Kc1 196. Qh6+ Kb1 197. Qg1+ Bc1 198. Qd2 Rh3 199. Bxc6 Rh2 200. Bd7 Rh3 201. Bxh3

White plays c4+, then continually checks the black king (who alternates between shuttling back and forth between b1 and c1 with the bishop on b2, and shuttling between b1 and b2 with the bishop on c1) while maneuvering the WQ from g6 first to capture the Nh7, then the Pb4, then the Nb7, then eventually to check black at g1 and force 29...Bc1.  Play then goes 30. Pa6 Kb2 and White executes a zigzag up to g7, then checks on b7 (forcing 38...Bb2 once again), then checks on h7 and zigzags back to play 47. Qg1+ and force Bc1 again, taking another 'free move' to play 48. Kf8.
This same maneuver (zigzag up to g7, check on b7 inducing Bb2, zigzag to check on g1, forcing Bc1, then take a 'free move' when Black's best play is Kb2) repeats as White plays 66. Ke8, 84. Kd8, 102. Kc8, 120. Kb8, 138. Kxa7, 156. Kb8, 174. Pa7, and 192. Pa8Q; play concludes with Qd4+, Q-b7-h7-h6+, Qg1+, and 198. Qd2 Rh3 199. Bxc6 Rg3, 200. Bd7 Rh3 201. Bxh3 stalemate.
(This problem comes out of The Problemist, by CJ Morse.)

Aloril has created what he calls “mobility chess” and generated up to 5-man tablebase for it. It just so happens that it generates shortest forced stalemates when there is one and there is no possible mating sequence.
Here are the extracted statistics provided for the longest forced stalemate sequences of 3, 4, and 5 unit positions.
3 man:
[Title "KPvK, stalemate, 42 ply"]
[StartFlipped "0"]
[FEN "8/8/8/8/8/1k6/7P/K7 b - - 0 1"]

1...Kc4 2. Kb1 Kd3 3. Kc1!! Ke4 4. Kd1 Kd3 5. Ke1! Ke3! 6. Kf1! Kf3! 7. Kg1! Kf4! 8. Kf2 Kg4! 9. Kg2! Kh4! 10. h3! Kh5! 11. Kg3! Kg5! 12. h4+! Kf5 13. Kf3!! Kf6! 14. Kf4 Kg6! 15. Kg4! Kg7 16. Kg5! Kf7 17. h5! Kg7! 18. h6+! Kf7 19. Kf5!! Kf8! 20. Kf6 Kg8!! 21. Kg6! Kh8!! 22. h7! *

4 man:
[Title "KPvKP, stalemate, 53 ply"]
[FEN "K7/8/5p2/8/8/8/1P6/5k2 w - - 0 1"]

1. b4!! f5 2. b5!! f4 3. b6!! f3 4. b7!! f2 5. b8=Q!! Kg2! 6. Qb2 Kg1! 7. Qd4! Kg2! 8. Qg4+! Kh1 9. Qf3+ Kg1!! 10. Qg3+! Kf1! 11. Ka7 Ke2! 12. Qg2 Ke1!! 13. Qe4+! Kd1 14. Qd3+ Ke1!! 15. Qe3+! Kf1!! 16. Kb6! Kg2! 17. Qe2 Kg1!! 18. Qg4+! Kh1 19. Qf3+ Kg1!! 20. Qg3+! Kf1! 21. Kc5! Ke2!! 22. Qh2! Kf3!! 23. Qh5+! Kg2!! 24. Qg4+! Kh1 25. Qf3+ Kg1!! 26. Qg3+! Kh1!! 27. Qxf2! *

5 man:
[Title "KQPvKQ, stalemate, 210 ply"]
[StartFlipped "0"]
[FEN "3q4/7Q/2K5/8/7k/8/4P3/8 b - - 0 1"]

1...Kg5!! 2. Qg7+!! Kh4! 3. Qh6+! Kg4! 4. Qe6+ Kf4!! 5. Qf7+! Ke5! 6. Qh5+! Kd4!! 7. Qg4+!! Kc3! 8. Qf3+!! Kb4 9. Qe4+ Kc3!! 10. Qe3+! Kc2!! 11. Qf3! Qa8+ 12. Kd6!! Qd8+! 13. Ke5! Qc7+ 14. Kf5! Qd7+ 15. Kf4 Qc7+! 16. Kg4! Qg7+!! 17. Kh3 Qh8+! 18. Kg2 Qg7+!! 19. Kf2! Qd4+! 20. Qe3! Qh4+! 21. Kg1 Qg4+! 22. Kf1! Qc4! 23. Qe5! Kd2! 24. Qg5+! Kd1! 25. Qd8+! Kc2! 26. Qf6! Kb3! 27. Kf2!! Qc5+! 28. Kg2!! Kb4 29. Qe6!! Kb5! 30. Kf3! Qh5+! 31. Kf4! Qh4+!! 32. Qg4! Qf2+! 33. Ke4!! Kb6 34. Qe6+! Kc7!! 35. Qc4+! Kb7! 36. Ke5! Qh2+! 37. Kd5!! Qh5+! 38. Kd6!! Qh2+! 39. Ke7! Qe5+! 40. Qe6!! Qg7+!! 41. Kd6! Qc7+! 42. Kd5!! Qd8+! 43. Ke5! Qg5+!! 44. Kd6! Qg3+!! 45. Kd7! Qg7+!! 46. Qe7! Qd4+!! 47. Ke6+!! Kc6 48. Qe8+!! Kc5 49. Qf8+! Kc6! 50. Qf3+! Kc7! 51. Qg3+! Kc6! 52. Qg2+! Kc7! 53. Qh2+! Kc6! 54. Qh1+! Kc5! 55. Qc1+!! Kb6! 56. Qb1+!! Ka7! 57. Qh7+! Ka8! 58. Qf5! Qb6+!! 59. Kf7! Qc7+! 60. Kg6! Qc6+! 61. Kg5! Qg2+! 62. Qg4!! Qd5+!! 63. Kh4! Qh1+! 64. Kg3! Qg1+! 65. Kf3! Qf1+! 66. Ke4! Qb1+! 67. Kf4! Qb4+ 68. Kf3! Qb3+ 69. e3! Qd1+! 70. Kg3! Qg1+! 71. Kf4! Qh2+! 72. Kf3! Qh1+! 73. Qg2! Qh4 74. Qg8+! Kb7! 75. Qf7+! Kc8! 76. Qf5+! Kd8!! 77. Qf8+! Kd7!! 78. Qg7+! Kc6! 79. Qg6+!! Kb5! 80. Qf5+! Kb6! 81. e4! Kc6! 82. Qe6+ Kc5 83. e5! Qd4! 84. Qf6! Kb5! 85. Qg5! Kc6! 86. Qe3! Qa1! 87. Kf4! Qa2 88. Qe4+! Kd7! 89. Qf5+! Ke8! 90. Kg5! Qb3! 91. Qg6+ Kd7 92. Qf6! Qa2 93. Kh6! Qe6! 94. Kh7 Qe7+! 95. Kg6! Qe6! 96. Kh6! Qa2 97. Kg7! Qe6!! 98. Qf7+! Qe7!! 99. Kg6!! Kd8!! 100. Qxe7+! Kxe7!! 101. Kf5! Kf7!! 102. e6+! Ke7! 103. Ke5!! Ke8!! 104. Kd6 Kd8!! 105. e7+! Ke8!! 106. Ke6!! *

I'm sure this problem has been posed before, but let's see how far we can get. I assume White will try to stalemate Black as quickly as possible, and Black tries to stave it off as long as possible.
[FEN "8/p1p1p1p1/2p5/2p5/2p5/2K5/p3P1P1/k7 w - - 0 1"]

1. Kc2 e6 2. e4 e5 3. g4 g6 4. g5 c3 5. Kc1 c2 6. Kxc2 c4 7. Kc1 c3 8. Kc2 c5 9. Kc1 c2 10. Kxc2 c4 11. Kc1 c3 12. Kc2 c6 13. Kc1 c2 14. Kxc2 c5 15. Kc1 c4 16. Kc2 c3 17. Kc1 c2 18. Kxc2 a6 19. Kc1 a5 20. Kc2 a4 21. Kc1 a3 22. Kc2

White needs to go back and forth between c2 and c1 with his King, but can try to move his pawns forward to speed up the process. Black just pushes his pawns one step at a time.

Yes this is the kind of position I'm looking for.  Here is another one [FEN "8/ppp1p3/4p3/4p3/8/8/1pp5/brk1K3 w - - 0 1"]

@michaelc35 Your own example is better, you should post it as an answer.

Where did you find the verb "pendle"? I can guess the meaning from context but I couldn't find it in my desk dictionary or the OED. Is this chess jargon?

@bof taken from my native language. As it is derived from the Latin pendulum I thought it made sense in English as well.

Is a legal position required? Black has 8 pawns on the board; which is the pawn that started on h7

You're right, I overlooked that. It was intended to be a legal position.

Here is a new record of 41 moves. I retooled the White knight checking cycle with a new scheme.
[Title "me, chess.stackexchange.com 8/25/2019, White Draws"]
[FEN "6r1/p1p1p1r1/p1p1p1q1/4pN1N/4n3/7K/4N1p1/R4Nbk w KQkq - 0 1"]

1. Nhg3+ Qxg3+ 2. N5xg3+ Rxg3+ 3. Nexg3+ Rxg3+ 4. Nxg3+ Nxg3 5. Kxg3 e4 6. Kh3 e3 7. Kg3 e2 8. Kh3 e1=Q 9. Rxe1 c5 10. Kg3 c4 11. Kh3 c3 12. Kg3 c2 13. Kh3 c1=Q 14. Rxc1 e5 15. Kg3 e4 16. Kh3 e3 17. Kg3 e2 18. Kh3 e1=Q 19. Rxe1 c6 20. Kg3 c5 21. Kh3 c4 22. Kg3 c3 23. Kh3 c2 24. Kg3 c1=Q 25. Rxc1 a5 26. Kh3 a4 27. Kg3 a3 28. Kh3 a2 29. Kg3 a1=Q 30. Rxa1 e6 31. Kh3 e5 32. Kg3 e4 33. Kh3 e3 34. Kg3 e2 35. Kh3 e1=Q 36. Rxe1 a6 37. Kg3 a5 38. Kh3 a4 39. Kg3 a3 40. Kh3 a2 41. Ra1


text:
Threefold repetition: Am I getting it right?

I was wondering if this is the right way of how the threefold repetition works. Thanks. (The image is in gif format, it should play automatically.)

In your gif the position is repeated four times. Black can claim a draw when the counter is at 2.

Leo, you have voted as "Best Answer" an answer which has been downvoted by 3 different people, because it incorrectly demonstrates when a draw may be claimed, causing readers to believe that more occurrences are needed than are, in fact, required. This is, strictly speaking, misinformation, and should not remain designated as the "best answer" when these facts reveal that it is not a good answer.

Insufficient information about the position. It might be ok, or the draw could have been claimed a move earlier already.

This animation is horrible, it'd be better to use the traditional move format

The confusion regarding the right to claim a draw when the position occurs 3 times results from the common misnomer for the situation: "Three-Fold Repetition".  A correct term could be Three-Fold Occurrence.
As a result, in your diagram, after there have been 2 repetitions (which shows in the animation as "Repitition (sic) 2", there have been 3 occurrences of the position, and a draw may be claimed.  The game is not actually "drawn" until a claim is made and the Arbiter or Tournament Director approves the claim. This also has the result that if the player creating the 3rd occurrence of the position neglects to make the claim and proceeds to make a move, the right to claim a draw for this situation expires instantly, with his move.
Note that the protocol for making such a claim must be (to avoid causing his right to claim to expire) the following: The player announces his intention to make the move and cause the 3-fold occurrence, makes the claim to the TD before moving, and the claim is adjudicated. The rules do not describe whether the TD will require the player to make the move, but it would seem that he must, for the claim to be completed, or he will not have fulfilled his claim by causing the position to appear.  If it is determined (after the move has been made, presumably) that the position is not in fact a third occurrence, presumably his move must stand, and a penalty for incorrect claim would be levied.
Note that all of the legal moves in all of the 3 occurrences must be identical, including rights to castle as well as any possibility of en passant capture.  It is not sufficient that the same pieces merely appear on the same squares.

Because of your last sentence, it is not sure if the claim could be made any earlier. :)

The player has to write down the intended move and that is sufficient for the claim to be accepted. It's moot whether the move is actually played on the board in the event of a successful claim.

For the last paragraph you could also mention that the same player must have the move!

@M.M It shouldn't be necessary. If all of the legal moves match, then the same player must be on move.

@M.M Your point about writing the intended move only works if the TD intends to approve the claim. What if they do not? Then they must require that the player make the move, since that is in fact what the rule requires; that the position recur on the board.  Only when the move is made can the claim be disallowed, and a penalty then enforced (and there certainly is one for such an invalid claim). So, I respectfully disagree.

@jaxter If the claim is rejected then the player must make the move that was written.  But if the claim is accepted, the game ends. Therefore the player does not have to make the move, since the game has ended already.

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


text:
Can you recommend a variation in the English opening for a technical player?
I'm looking to study the English opening. To cut down my homework, I would like to focus on one or two variations.
Why am I interested in the English opening, I hear you cry? Mostly because I want to vary my games a bit*. I'm a fan of 1. d4 and 1. c4 has transpositional possibilities to 1. d4 openings.
Can you recommend a variation of the English opening that suits my playing style?. Any references to books, videos, top players who employed the line etc. are appreciated too.

Player background

Rated 2100 Elo
Technical playing personality. Preference for positional, intuitive moves and the endgame
Currently using queen pawn openings, e.g. Slav Mainline Dutch, Queen's Gambit Accepted: 3. e4, Queen's Gambit Declined: Lasker Variation
As Black I use the Caro-Kann and Slav
Have experimented with the English Botvinnik system, but I don't like how Black can get easy equality

*Oh, I'm also English too...

It's going to be hard to give one single variation (just like you can't play a single variation as white after 1.e4 either). There's at least 1...e5, 1...c5 and others to deal with. If you want to transpose to 1.d4, are you looking to avoid any specific 1.d4 move orders?

It's a good question. Just a quick answer with some thoughts to give you some starting ideas, hopefully to be improved later.
I've always liked the English exactly for its rich transpositional possibilities, they're endless aren't they?
Your intent to divert towards d4 lines via the English is very common. For example Magnus Carlsen often employs it to avoid main theory lines (it's very hard to prepare against 1.c4). So make sure you look into his games on 1.c4. Some exemplary games off the top of my head:
One of the 2013 world championship matches (specially because you're a d4 player and you seem to like endgames): Notice how by move 7 we've reached a completely off-book position, though very natural to play for white:
[FEN ""]
[Event "WCh 2013"]
[Site "Chennai IND"]
[Date "2013.11.15"]
[Round "5"]
[White "Carlsen, M."]
[Black "Anand, V."]
[Result "1-0"]
[ECO "D31"]
[WhiteElo "2870"]
[BlackElo "2775"]
[PlyCount "115"]
[EventDate "2013.11.09"]
[EventRounds "10"]
[EventCountry "IND"]
[Source "Mark Crowther"]
[SourceDate "2013.11.18"]

1. c4 e6 2. d4 d5 3. Nc3 c6 4. e4 dxe4 5. Nxe4 Bb4+ 6. Nc3 c5 7. a3 Ba5 8. Nf3 Nf6 9. Be3 Nc6 10. Qd3 cxd4 11. Nxd4 Ng4 12. O-O-O Nxe3 13. fxe3 Bc7 14. Nxc6 bxc6 15. Qxd8+ Bxd8 16. Be2 Ke7 17. Bf3 Bd7 18. Ne4 Bb6 19. c5 f5 20. cxb6 fxe4 21. b7 Rab8 22. Bxe4 Rxb7 23. Rhf1 Rb5 24. Rf4 g5 25. Rf3 h5 26. Rdf1 Be8 27. Bc2 Rc5 28. Rf6 h4 29. e4 a5 30. Kd2 Rb5 31. b3 Bh5 32. Kc3 Rc5+ 33. Kb2 Rd8 34. R1f2 Rd4 35. Rh6 Bd1 36. Bb1 Rb5 37. Kc3 c5 38. Rb2 e5 39. Rg6 a4 40. Rxg5 Rxb3+ 41. Rxb3 Bxb3 42. Rxe5+ Kd6 43. Rh5 Rd1 44. e5+ Kd5 45. Bh7 Rc1+ 46. Kb2 Rg1 47. Bg8+ Kc6 48. Rh6+ Kd7 49. Bxb3 axb3 50. Kxb3 Rxg2 51. Rxh4 Ke6 52. a4 Kxe5 53. a5 Kd6 54. Rh7 Kd5 55. a6 c4+ 56. Kc3 Ra2 57. a7 Kc5 58. h4 1-0

But it must be admitted that Magnus makes these endgames look easy when for us it's a nightmare to convert.
Personally I really like the Catalan and Larsen transpositions, so I would definitely recommend those. The Catalan and all its variants are very natural to play (with sound endgame structures, because you always have a choice how you commit your central pawn strcuture, unlike most other d4 lines).
Two other examples that come to mind, are the two times Magnus employed 1.c4 vs Nakamura in classical chess:
One leading to a Catalan with a delayed d4:
[FEN ""]
[Event "8th Tal Memorial"]
[Site "Moscow RUS"]
[Date "2013.06.22"]
[Round "8.5"]
[White "Carlsen, M."]
[Black "Nakamura, Hi"]
[Result "1-0"]
[ECO "A13"]
[WhiteElo "2864"]
[BlackElo "2784"]
[PlyCount "93"]
[EventDate "2013.06.13"]
[EventRounds "9"]
[EventCountry "RUS"]
[EventCategory "22"]
[Source "Mark Crowther"]
[SourceDate "2013.06.24"]

1. c4 e6 2. g3 d5 3. Bg2 c6 4. Qc2 Nf6 5. Nf3 dxc4 6. Qxc4 b5 7. Qb3 Bb7 8. O-O Nbd7 9. d4 a6 10. Ne5 Qb6 11. Be3 c5 12. Nxd7 Nxd7 13. d5 e5 14. a4 b4 15. Nd2 Bd6 16. Nc4 Qc7 17. f4 O-O 18. Rac1 exf4 19. Bxf4 Bxf4 20. gxf4 a5 21. e4 Rae8 22. e5 Ba6 23. Rfe1 Kh8 24. Nd6 Re7 25. Qe3 Qd8 26. b3 g5 27. Kh1 Qb8 28. Qf2 gxf4 29. Qxf4 Bd3 30. Re3 Bg6 31. Rf1 Rxe5 32. Rxe5 Qxd6 33. Re8 Qxf4 34. Rxf8+ Kg7 35. Rxf4 Kxf8 36. d6 Ne5 37. Bf1 Bc2 38. Bb5 f5 39. Kg2 c4 40. Bxc4 Be4+ 41. Kg3 Nxc4 42. bxc4 Ke8 43. c5 Bc6 44. Rxf5 Bxa4 45. Re5+ Kd8 46. Re7 Bc6 47. Rc7 1-0

The second leading to a Larsen (1.b3) type of middlegame: (with black playing the Dutch)
[FEN ""]
[Event "2nd London Chess Classic"]
[Site "London ENG"]
[Date "2010.12.11"]
[Round "4"]
[White "Carlsen, M."]
[Black "Nakamura, Hi"]
[Result "1-0"]
[ECO "A10"]
[WhiteElo "2802"]
[BlackElo "2741"]
[PlyCount "117"]
[EventDate "2010.12.06"]
[EventRounds "7"]
[EventCountry "ENG"]
[EventCategory "19"]
[Source "Mark Crowther"]
[SourceDate "2010.12.13"]

1. c4 f5 2. g3 Nf6 3. Bg2 d6 4. Nc3 g6 5. e3 Bg7 6. Nge2 O-O 7. O-O e5 8. b3 Nbd7 9. d3 c6 10. Ba3 Qc7 11. Qd2 Re8 12. Rae1 Nc5 13. h3 e4 14. dxe4 Nfxe4 15. Qc2 Nxc3 16. Nxc3 Be6 17. Rd1 Rad8 18. Bb2 Bf7 19. Rd2 a5 20. Rfd1 Be5 21. Ne2 a4 22. b4 Nd7 23. Bd4 Nb6 24. Bxb6 Qxb6 25. Rb1 Qc7 26. Nd4 Rc8 27. Rc1 Qe7 28. Rd3 c5 29. bxc5 Rxc5 30. Qxa4 Rec8 31. Rb1 Rxc4 32. Qd1 b6 33. Nb5 R4c5 34. Nxd6 Bxd6 35. Rxd6 Bxa2 36. Ra1 Rc1 37. Rxc1 Rxc1 38. Rxg6+ hxg6 39. Qxc1 Qd6 40. h4 Bf7 41. h5 Kh7 42. hxg6+ Kxg6 43. Qc2 b5 44. g4 Qe5 45. gxf5+ Kg7 46. Qe4 Qd6 47. Qh4 Bc4 48. Bf3 Qf6 49. Qxf6+ Kxf6 50. Be4 Ba2 51. f4 b4 52. Kf2 b3 53. Bd5 Kxf5 54. Kf3 Kf6 55. e4 Kg6 56. Ke3 Kh5 57. Kd4 Kg4 58. f5 Kg5 59. Ke5 1-0

Here's another 1.c4 into Catalan, though it was only a rapid: Notice how white intentionally delays the pawn to e3 committment until black has made a decision with the b4 bishop (8...Bc5 now you repond with e3. Otherwise, with the black e4 pawn, a preemptive e3 would weaken your light squares). This is a good example of what I meant earlier with "not committing too early" with the pawn structre you want to achieve.
[FEN ""]
[Event "Amber Rapid"]
[Site "Nice FRA"]
[Date "2008.03.22"]
[Round "7"]
[White "Carlsen, M."]
[Black "Anand, V."]
[Result "1-0"]
[ECO "A20"]
[WhiteElo "2733"]
[BlackElo "2799"]
[PlyCount "95"]
[EventDate "2008.03.15"]
[EventType "rapid"]
[EventRounds "11"]
[EventCountry "FRA"]
[EventCategory "21"]
[Source "Mark Crowther"]
[SourceDate "2008.03.24"]

1. c4 e5 2. g3 c6 3. d4 e4 4. d5 Nf6 5. Bg2 Bb4+ 6. Bd2 Qe7 7. Nc3 O-O 8. a3 Bc5 9. e3 d6 10. Nge2 cxd5 11. Nxd5 Nxd5 12. cxd5 Nd7 13. O-O Nf6 14. Bc3 Bg4 15. Bxf6 Qxf6 16. b4 Bb6 17. Bxe4 a5 18. bxa5 Rxa5 19. Bxh7+ Kxh7 20. Qb1+ g6 21. Qxb6 Rfa8 22. Qd4 Qf3 23. Nc3 Re8 24. h3 Bf5 25. Qf6 Kg8 26. Rab1 Rxe3 27. Rxb7 Bc8 28. Qd8+ Kg7 29. Qxc8 Rxc3 30. Rxf7+ Kxf7 31. Qd7+ Kf6 32. Qd8+ Kf5 33. Qxa5 Rxa3 34. Qb4 Ke5 35. Qd2 Rd3 36. Qg5+ Qf5 37. Re1+ Kxd5 38. Qxf5+ gxf5 39. Kg2 Ra3 40. h4 Kd4 41. h5 d5 42. h6 Ra7 43. Kf3 Rh7 44. Re6 Kc3 45. Rc6+ Kd3 46. Kf4 Rf7 47. Kg5 Ke2 48. Rd6 1-0

Here's a crazy one: a 1.c4 turning into a Caro-Kann leading into a IQP middlegame:
[FEN ""]
[Event "Corus A"]
[Site "Wijk aan Zee NED"]
[Date "2009.01.31"]
[Round "12"]
[White "Carlsen, M."]
[Black "Smeets, J."]
[Result "1-0"]
[ECO "B10"]
[WhiteElo "2776"]
[BlackElo "2601"]
[PlyCount "57"]
[EventDate "2009.01.17"]
[EventRounds "13"]
[EventCountry "NED"]
[EventCategory "19"]
[Source "Mark Crowther"]
[SourceDate "2009.02.02"]

1. c4 c6 2. e4 d5 3. exd5 cxd5 4. cxd5 Nf6 5. Nc3 Nxd5 6. Nf3 Nc6 7. Bb5 e6 8. O-O Be7 9. d4 O-O 10. Re1 Bd7 11. Bd3 Rc8 12. Nxd5 exd5 13. Ne5 Bf6 14. Bf4 g6 15. Qb3 Na5 16. Qb4 Be6 17. Bh6 Bg7 18. Bxg7 Kxg7 19. h4 Re8 20. h5 f6 21. Nf3 b6 22. Bb5 Re7 23. Re2 Rcc7 24. Rae1 Kf7 25. Qd2 Qf8 26. Qf4 Bf5 27. g4 Bc8 28. b4 Nb7 29. Bc6 1-0

The list can go on, but it's up to you to carefully study these games and figure out which ones really suit your style of playing, no one can know it better than yourself.
As for the English-Botvinnik system, I'm surprised you don't like it, it's a sharp weapon specially in faster time controls, just watch how Nakamura plays it frequently in blitz. I recently read this article on the Botvinnik variation on chess.com, it may change your mind.
Another very interesting use of the English is to dodge the Grünfeld, as it is also pointed out on the wikipedia page, e.g.: 1.c4 Nf6 2.Nc3 g6 3.e4... But there are many such examples and that's why the English is so much fun to play.
Finally, there's one response that I dislike the most vs 1.c4, and that is 1...e5 leading sometimes to a reversed Sicilian...This is an example of black making use of the versatility of the English. But even if black decides to not play the Sicilian, a simple plan with e5 Nf6 Bc5 d6 a6 and tucking the bishop back to a7 is not obvious to face as white. So make sure you have a line (or at least some ideas) vs this.
This was just to give you some ropes. You will have lots of fun playing the English opening, and the more you play it the more resourceful you'll become with it, and hopefully you'll grow to appreciate its unique potentials. Enjoy!

I started playing the English a short time ago, too. I used to play the London System before, and I found that at a certain level I had to fight for equality as white. I think my playing style fits yours too and I was advised to move to the English opening with g3. I'm currently rated 1912 ELO by FIDE, in case this info is useful for you.
With this repertoire in mind I've found the books by Mihail Marin "The English Opening" from the Grandmaster Repertoire series extremely useful. Despite its name (Grandmaster Repertoire made me think they would be too advanced for me) I found these books fit my needs perfectly, Mihail's explanations of plans and structures are clear and easy to understand and he builds a complete repertoire based in 1.c4 and 2.g3.

Thanks for the recommendation. As an aside, I read Marin's 'Secrets of Attacking Chess' a while ago. I liked it, so I'll probably like your recommended book too.

Most people try to transpose into their d4 defense to reduce study time and for the most part, if white refuses to play d4 the lines are fine for black.
The symmetrical is probably okay but I try to avoid symmetrical lines.
e5 is the principled "correct" move. Its basically a reversed Sicilian. If you're a 1e4 player it shouldn't be hard to come up with something that mirrors what you play vs the Sicilian. I Usually play a reversed closed or great snake depending on the move order

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


text:
Why does White play 13. f3 and not 13. f4 in the Modern Benoni, Classical Line?
In the classical line, the book Starting Out: Modern Benoni by Endre Vegh recommends 13. f3:
[FEN ""]
[StartPly "26"]

1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. Nf3 g6 7. e4 Bg7 8. Be2 O-O 9. O-O Re8 10. Nd2 Na6 11. Kh1 Nc7 12. a4 b6 13. f3 (13. f4)

This is what the author says of 13. f3:

the centre is thereby strengthened and will not be easily undermined.

But given that White would like to push with e5, why not support it with 13. f4 beforehand?

I played this position many times with white and f3 is really good move here.
It is not only about what white wants, but also about what black wants. You have more space and so you can choose easier from more plans. You can play for Rb1 b4, you can play for g4, you can play for f4 and e5. Black has not that much space and can't choose from many plans.
Now look at the position. Who will be happy to see f4 and potentially e5? Probably you in the beginning, but then also Qd8, Re8, Nf6 and Nc7. That is quite a body count. They don't have much work now but will have plenty of job after you weaken the centre. What about your pieces? Both knights will lose part of its mobility as they will have to protect pawn on e4. Bishop on c1 will hate you. Maybe you will help Rf1, while Qd1 and Be2 will see also slight improvement of their chances, but simple adding pros and cons of f4 action compared to f3 should lead to clear NO!. You won't loose the e4 pawn just by playing f4 or anything like that, but by this overextending on part of board where you really are not stronger, you achieve nothing positive at all.
The plan is good only when it helps you more than your opponent!
The f3 alternative with killing opponent's bishop immediately on c4 (f3 Ba6 Nc4 Bxc4 Bxc4 is the main line and for good reason, as black can't afford you to play b3 and retake on c4 with pawn!) saves you material advantage of bishop vs. knight, doesn't commit you to anything and then you can calmly go either for Rb1 b4 or some other stuff depending on black answer.

Ok I was writing about slightly different version of this variation (position with f3 instead of Kh1) but the general idea that you help more to your opponent than yourself is right. In the morning I was surprised how is it possible to postpone f3 for so long and now I see I analysed wrong position. So at least the Ba6 with Bxc4 doesn't apply here. Sorry for mistaking you.


text:
Deleting multiple games from a large PGN file
I have spent around half an hour searching Google and I have not found what I am looking for -perhaps I did recognise it as what I needed if I had come across it. I have just recently downloaded SCID and decided to add all of my games from Chess.com as a starter to a database.
After combining all the separate PGN files into one, I used the utility that comes with SCID to convert it into the SCID database format. Along with the output of that utility is a file -.err format- of errors -if any- that occurred during conversion. While the number of errors I got is not much, it is large enough for it be a complicated process if I went through and deleted the games by hand.
An example from the first three lines of the error file (1 game):
my_games.pgn:(game 383, line 10658) Error: Invalid FEN: rnqkrbbn/pppppppp/8/8/8/8/PPPPPPPP/RNQKRBBN w EAea - 0 1

my_games.pgn:(game 383, line 10658) Error reading tag: [FEN "rnqkrbbn/pppppppp/8/8/8/8/PPPPPPPP/RNQKRBBN w EAea - 0 1"]

my_games.pgn:(game 383, line 10663) Error reading move in game graffitivisuals - walidmujahid, 2012: Ng3

Is there a utility out there where I could simply pass my PGN file though it and specify the game number -multiple- to delete. I am still new to SCID, so perhaps did I miss the fact that SCID has something that can help with this matter?
Any guidance on this would be most appreciated.
Post Script: GitHub was among the places that searched for such a utility, though, without fruition. If, perhaps, there is a script that comes remotely close to doing what I described, or perhaps even does exactly what I need, any guidance towards that script would also be most appreciated.

I think that if you just create a new database in Scid, then import the PGN file into it, it just skips all the games with errors. Wouldn't that work?

Is this a Chess960/Fischer game?

@RemcoGerlich Yes, that works, however, for larger databases loading the full PGN file would be rather slow and it is my understanding that converting it to the si4 format makes it more efficient within the program itself -I may be mistaken.

@Marco Now that I think about it, I did have a few 960 games in my chess.com download. I did not even think about it, but I am aware that 960 does not work in SCID -SCID vs PC to be more accurate,

@WalidMujahid: importing it into a database within Scid also converts it so si4 (that is the format of Scid databases after all). It probably uses the exact same code.

@RemcoGerlich I see.

A PGN file is simply a flat text file, which can be created/edited using a text editor (I use Notepad++).

ANSWER: While using a text editor may not be optimal, or may not be an automagical way of many specific games from a large PGN file, it works.  I don't know of a text editor specifically designed to deal with PGN files otherwise.  Also, SCID itself allows you to delete games from a collection.  Notice in this link the option to delete current game?

I would also observe that the FEN you've posted is only valid if you're playing Fischer (or 'random') Chess where the pieces are randomly placed at the beginning.  Copy your FEN HERE and observe that while valid FEN, is not a valid opening position for a regular game.
The problem with your file is that it is mixing regular and Fischer chess games..

Maybe use the free Chessbase Reader and import/open the file. That might work.

For the specific requirement to filter out Chess960 games from a PGN file, you could use pgn-extract.pgn-extract home page Since such games necessarily include a SetUp tag, the --nosetup argument of pgn-extract allows them to be filtered out. The same argument could be used to remove any game that has a non-standard starting position.
Disclosure: I am the author of pgn-extract.


text:
What is the number of chess position for each move?
I have read some articles that chess has a numbers of 10 to power of 120. Can some one can throw lights to it:
White 1st move: No of Position
White 2nd move: No of Position
till
White 72nd move: No of Position
Similarly for Black
Black 1st move : No of Position
Black 2nd move : No of Position
Till
Black 72nd move : No of Position
Your help will improve one's chess understanding better and will bring some hope to readers relating to chess can be solved.
Thank you for your time Raman Thanks for the first answer

You are misusing the word "probability" in your question. 10 to the power 120 is known as the Shannon number and is a lower bound for the game-tree complexity (number of different games of chess). This has nothing to do with probability. Also this number of different games is not the same as the number of possible chess positions (which is estimated as 10^43).
If you look at the starting position in chess, each player has 20 possible moves (16 with the pawns and 4 with the knights). So the number of possible games of 1 move (2 plies, i.e. one white move and one black move) would be 20*20 = 400 already.
Now the number of possible moves increases initially because your pieces get more space. The number of possible second moves is not fixed, but will depend on the first move. So it is impossible to give an exact answer to your second question. But you can do some estimates...
If you say that at each move you have a choice between 30 moves (this is an estimate) and if you say that an average chess game lasts 40 moves (80 plies), you end up with the number of possible games equal to: 30^80=(30^2)^40 which is approximately equal to 1000^40=10^120.
This is a very rough estimate but is sufficient to show that chess is incredibly complex and is not going to be solved anytime soon.
You might also like the Numberphile episode on the topic

Where is the proof, that 10^120 is a lower bound to the number of possible chess games? This statement certainly does not follow from Shannons extremely rough estimate.

@SimonFromme: No proof as such, but Shannon in his paper says that the number of around 30 possible moves is fairly constant throughout a game (empirical evidence from master games) and also says that the number of 40 moves for a game is rather conservative, since in this context one need to consider the number of moves until mate not until resignation.

Well that is nothing that would justify saying "10^120 is a lower bound for the game-tree complexity". All this is is a rough semi-educated guess.


text:
What are the main differences between 2...d5 and 2...e5 in the anti-Caro-Kann?
In the anti-Caro-Kann (also known as the Pseudo Panov-Botvinnik or Panov's little Brother), reached by 1. e4 c6 2. c4, what are the main differences between 2...d5 and 2...e5?
[FEN ""]
[StartPly "4"]

1. e4 c6 2. c4 d5 (2...e5)

The reason why I ask this question is because I play the Black side of this opening, using 2...d5, as suggested in The Caro-Kann: Move-by-Move. I also own The Panov-Botvinnik: Move-by-Move, which covers 2...e5 but from White's point of view, so Black ends up making a mistake, or the author annotates the White moves more heavily.

They are based on two different strategies - in the e5 line, black focuses on preventing (or making less favourable) the d4 central grab. Black may continue with Bc5, d6, Qc7 (defending laterally), Nf6, Nbd7, Be6. White has a small space advantage thanks to ownership of d5 but probably not a lot more. It's a slow but solid development plan.
In the d5 line, black seeks to clarify the centre straightaway. After 1. exd5 cxd5 2. cxd5 black has some open lines and leaves white with an isolated queen pawn, however, after 2...Qxd5 3. Nc3 and 4. d4 white has a small development advantage. The game becomes about whether white's development advantage outweighs the potential weakness on d4.

I don't play this from either side, but apparently 2... d5 leads to positions known as isolated queen pawn (isolani) which can also result from many other openings. Look it up, there is lots of information out there about this. There is a fairly standard plan in these positions. White wants to avoid getting into an endgame where the pawn would be a weakness. Typically black would try to control the square in front of the isolani (i.e. d5 in this case) preventing white from exchanging the pawn playing d5 himself. White usually has a bit more active play in the middle-game.
I don't like 2...e5. If white attacks the e5 pawn, e.g. with 3. Nf3, black is almost forced to play 3...d6 and the set-up with pawns on e5,d6 and c6 is gernerally not good. White can later play d4 and open the d-file after which the pawn on d6 might get weak.

There is also plenty of lines in 2...d5 that are not IQP.

+1, as an isolani is common in the 2...d5 variation. To expand on @hoacin's comment, 1. e4 c6 2. c4 d5 3. cxd4 cxd5 4. exd5 Nf6 5. Nc3 Nxd5 then 6...Nxc3 doesn't result in an isolani.

@hoacin: In order to avoid IQP white would have to either play d3 or play 3. cxd5 cxd5 4. e5; neither of which seems very attractive to me.

@Bad_Bishop: And if black does not capture 6...Nxc3 ?

@user1583209: You're right, it's not obligated (chess isn't checkers), but Black usually plays 6...Nxc3 to play against the hanging pawns after bxc3 in an endgame (they are a slight structural weakness).

I didn't think white is the side to avoid IQP. IQP in Panov is quite dangerous for black as wrong knight is standing on d5. Black has those Nf6 Nc6 systems with either Bg4 or Be6 that lead to different positions and these systems are quite popular, in corr they are already ahead over lines with e6. Also in hanging pawns you want knight on f6 not on c6. The attack is unpleasant for black in all these e6 lines, even if they are of course perfectly playable.

There is nothing similar with these two variations. Panov is unbalanced open game, both sides have some pros and cons.
The e5 is weak move, it leads to something that I think is called old indian defence, KID with bishop on e7, which makes black setup way too passive. No pressure on h8-a1 diagonal, no pressure on the e-file, no kingside attack.


text:
Why did Shirov not trade bishop for knight in this position to play against doubled, isolated b-pawns?
In The wisest things ever said about chess by GM Soltis, he quotes this about tempi and gives the following example:

Tempi should not be counted but weighed.

[FEN "r2q1rk1/pp1b1nb1/n2p1pp1/3Pp2p/2N1P2B/2N2P2/PP2B1PP/R2Q1RK1 w - - 0 1"]
[Site "Istanbul"]
[Date "2000"]
[White "Gelfand"]
[Black "Shirov"]

  1. a4             Qb8
  2. Nb5 (2...Bxb5 3. axb5 Nc7)           Rc8
  3. Bf2            Bh6
  4. Qb3            Nc5
  5. Qa3             *

The point of the example is that white started with 2 extra tempi in a King's Indian structure, that allowed him to place pressure on the queenside.
My question is, why didn't black play 2...Bxb5 3. axb5 Nc7 to gain chances to win one of the b-pawns?

+1 because I think this is the kind of question we need more of.

Besides the answers so far: as often happens in such situations, this exchange in effect loses another  tempo because it lets White "develop" his QR to the half-open file without ever moving it.  Here White's space advantage on the Queenside also lets him pile up on that a-pawn much more quickly than Black can call up reserves to defend it.

After 4.Qb3 in your proposed line, there aren't any real chances to win the b5 pawn.  If Black continues to add pressure with ...Qe8, then after the knight on c4 moves, the bishop on e2 will provide enough protection to defend the b5 pawn.
In the meantime, white gets the advantages of the bishop pair, the semi-open a-file for his rook, and a black knight that has no future on c7.  Black doesn't appear to my eyes to have quick enough counterplay on the kingside while white can continue building up forces on the queenside and has a potential pawn break with the move b5-b6.  The resulting position in your proposed variation would be static and strategically miserable for black.

why didn't black play 2...Bxb5 3. axb5 Nc7 to gain chances to win one
  of the b-pawns?

1) The bishop on d7 is a particulerly fine bishop fighting for control of some very important white squares contested by white pawns. Getting rid of it seems a shame.
2) It's not clear that black is going to win the resulting white pawn on b5 any time soon and in the meantime it is very annoying indeed.
3) Maybe white is going to follow up with b6 and either that pawn is going to be a monster or if it is swapped off white is going to end up with a knight on b6 instead supported by the bishop which is going to move to f2. The white squared bishop is going to come to b5 and there is no corresponding bishop for black.
4) It is going to be difficult for black to compete for the a and c files.
All in all only a masochist is going to go down that route.


text:
Where do black's centre pawns and light square bishop belong in the symmetrical English?
I played a rapid game last night and got this symmetrical English position as black:
[FEN ""]
[StartPly "116"]

1. c4 c5 2. Nf3 Nf6 3. Nc3 Nc6 4. g3 g6 5. Bg2 Bg7 6. d4 cxd4 7. Nxd4 O-O 8. Nxc6 bxc6

I found it hard to know where to put my d and e pawns, and how to develop my light square bishop. So, thematically where do black's central pawns and light square bishop develop to and why?

If your opponent is the type to bring his own rope to commit a suicide, I would certainly go for Rb8 d6 Bd7 c5 and later a5 a4 setup, hoping knights will go off the board (on d5) as soon as possible ruining white's gueenside later in the style of Benko gambit, with equal material and stupid (but nice looking) bishop on g2 aiming to nowhere. Reasonable opposition will do everything to stop this plan so the game will certainly not be easy, especially white should stay with knight on c3 or a4, never exchanging it without good reason. Still Rb8 c6 d6 e7 Bd7 looks like setup I would call good plan. Then you just make usefull waiting moves. I don't like d5 plans much as it weakens c5 square making white the captain of the queenside. It is however respectable approach restricting g2 bishop and putting pawn to the center, different handling of the same position.

This does not seem symmetrical to me.
After 8...dxc6 you could have reached a symmetrical and very drawish position.
Playing 8...bxc6 seems more ambitious. Seems like black will want to play d5 sooner or later to get rid of that backward pawn on d7 and to limit the white bishop on g2. Depending on what white does, this might require to play e6 and/or to put the bishop on b7 to support d5 or to a6 to ask white how he wants to defend the c4 pawn. I don't see how the c8 bishop could find any good square along the h3-c8 diagonal anytime soon.

The opening is called Symmetrical English (1. c4 c5) even if the game becomes less symmetrical later.


text:
Is it ethical to spar against an engine when playing correspondence?
I started playing correspondence on chess.com purely for the fun of it and to gain some deep learning (i.e. there's no prize involved).
We are about 10 moves in and coming close to me being out of book. To help my learning, I'd like to set the position up against a computer and spar against that. I am not interested in the computer's evaluation, recommended moves for me etc. I'm really just interested in practicing from a specific position.
My question is, is it ethical to spar against a computer between moves in a correspondence game?

It would be completely ethical if you just wrote down the positions you're interested in practising and then actually did the practice after the game has ended.

Think of an examination. I am sure that many of us would be "interested" in the answers to exam questions during the exam. For some reason, that is not permitted.

Chess.com's site rules have the following to say:

You can NEVER use chess programs (Chessmaster, Fritz, etc) to analyze current ongoing games unless specifically permitted (such as a computer tournament, etc). The only type of computer assistance allowed is games databases for opening lines in Turn-based Chess and Vote Chess. [...]

So it boils down to the question if playing out positions from a corr game against an engine counts as analyzing.
The answer can only be "yes" because for some possible continuations of your game, the engine provides its best moves. This is clearly an act of analysis.
There will be plenty of time to play against your engine after the game jas finished.

Very clear. Thanks! In my case, my program is Chessmaster, so your answer leaves no doubt in my mind.

There might be workarounds, though. Naturally, you and your opponent are free to play a game under any rules you can agree between the two of you. You might have to take the game off the site, so as not to mislead their stats/rankings as to what kind of game is being played. And even if they agree, you might find your opponent takes the game less seriously knowing that you're messing with programs.

@SteveJessop they could also start using the same strategy, and gain even more advantage than you.

This answer addresses whether the rules allow something, which is often a different question than whether something is considered ethical.

@Weston: fortunately in this case the one seems to reduce to the other -- the questioner accepts that breaking the agreed rules of the game is unethical. If a life were at stake or whatever, then naturally the moral value of cheating at chess might be irrelevant, and we'd need a more complex (albeit probably still easy) ethical analysis :-)

In chess we have to find the best move to play. In order to achieve this, we calculate several moves ahead. By using a computer 'only for sparring' you're effectively limiting the depth of your search tree by half - namely the opponent's moves. This is not like starting the 100m sprint at the 50m line and asking if it's ethical, because the number of possible lines grows exponentially with the depth of the tree. It turns out using a computer for only your opponent's moves is more like starting the race 87m ahead.
On Chess.com specifically computers are never allowed (as the rules state), although correspondence chess usually allows computer analysis for all moves. See the lack of a rule against it in the International Correspondence Chess Federation (ICCF) Rules.

The answer is simple, and nobody has come out and said it:  NO.  Not ethical.  You need to either disclose to your opponent, find a way to save the game, and play with the computer later.  The reason it is not "ethical" is because the other player assumes they are playing a human only, that is the underlying assumption.  I don't think it is "terribly" unethical, but it kind of fits the very definition of unethical, it is violating the understanding between you and the other player.  Full disclosure will handle it, and the other player can decide to play or not.  My chess computer is so damn good, I can beat anyone, if I secretly use it!  Wish life itself were that easy.

If you want to do this, you must play on a site whose rules explicitly permit it. FICGS(www.ficgs.com) expects that its players, who call themselves 'centaurs', will use computer assistance to the maximum. I tried it for a while. Anyone who is not a geek will find it very tiring.

As mentioned, it's against the rules.  But if you just want to learn and have fun, just play against a computer in the first place.  Why even involve another human being?  You'll get the same practice benefits you want without any ethical concerns.

As others stated I think it depends on the server's rules.  If the server allows it then of course it isn't unethical.  If the server specifically states that you can't then its unethical.  You agree to their terms by playing on their server.
As you are sparring against the engine you will be influenced on how to make the next move in your current game.  Doesn't mean you had intentions of cheating just means, you analyzed the position and if you play to win, regardless if a prize is involved or not, you will naturally go against the move that isn't good to play because you sparred against, essentially, a super grand master and you want to win.  That isn't fair play to your opponent on a server that has rules against using a computer.
My suggestion would be, if you are on a server that has rules in place against using computers during play, make notes in your game where you want to analyze and analyze the game AFTER the match is over.

USCF correspondence chess rules forbid the use of computers except to record moves. In other words, you can not use the engine for any form of analysis.


text:
Is there any way to gain equality with the QGD Marshall Defence?
The Marshall defence goes 1. d4 d5 2. c4 Nf6?!
I played this game recently as white. It was the first time I saw the Marshall in a game and the real contest was over by move 14.
[FEN ""]
[StartPly "7"]

1. d4 d5 2. c4 Nf6 3. cxd5 Nxd5 4. Nf3 Bg4 5. e4 Nb6 6. Be2 Bxf3 7. Bxf3 e6 8. O-O Be7 9. d5 O-O 10. dxe6 fxe6 11. Qb3 Qd7 12. Bg4 Rf6 13. Rd1 Bd6 14. e5 Rg6 15. exd6 Rxg4 16. dxc7 Rd4 17. Rxd4 Qxd4 18. Qxe6+ Kf8 19. c8=R+ Nxc8 20. Qxc8+ Ke7 21. Qxb7+ Kf6 22. Qf3+ Ke6 23. Qe3+ Qe5 24. Nc3 Nc6 25. f4 Qxe3+ 26. Bxe3 a5 27. Rd1 Ne7 28. Nb5 Rb8 29. a4 Nd5 30. g4 Nxe3 31. Re1 Rf8 32. Rxe3+ Kd7 33. f5 g6 34. Rf3 Kc6 35. Kg2 gxf5 36. Rxf5 Rg8 37. Kf3 Rd8 38. Kg3 Rd3+ 39. Rf3 Rd2 40. b3 Rb2 41. Na3 Ra2 42. Nc4  1-0

Now the Marshall defence is considered to be dubious, even refuted:

This [1. d4 d5 2. c4 Nf6?! 3. cxd5 Nxd5 4. Nf3!] is considered to be the refutation for this defence

Source: GreenCastleBlock on YouTube, @ 0:58.
But my question is there any move after 4. Nf3 where black gains equality?

People have different opinions on what equal means. I recently won a game quite convincingly and fast against IM and he was pretty sure he equalized from the opening, knowing the line. Also my team mate told it is equal. The whole stage was around 0.2 and better  and the 'drawish endgame' was over 0.5 so with this definition of equality many things are equal. Once our team coach prepared me an equal line, I lost without even firing a bullet (it was 0.4 for my opponent I saw later) and since that time I ignore people saying equal. 0.00 has some meaning but equality is too broad.

22. Bd2 looks more convincing.

Black sometimes obtain very wild attacks in Marshall, thats why I play it in blitz sometimes.

The Marshall is considered dubious since Black essentially just gives up full control over the center.  For that reason, there is no move that would give Black absolute equality after 4. Nf3
There are probably good development schemes that would give Black a playable game, but there is no direct path to absolute equality.  Heck, there's no direct path to complete equality for Black in even the most respected openings, such as the Grunfeld and Slav.  Even in those openings Black has to work to achieve an equal game.
The best development scheme that I know of in the Marshall is the following (after 4. Nf3):
g6, Bg7, 0-0, Nc6, Bg4.  And if White plays e4 at any point, the Knight on d5 retreats to b6.  This gives Black a reasonable game, and I believe it is the most popular system in the reference database.  But even here, White keeps a comfortable edge.


text:
Is the advance Caro-Kann becoming less popular?
In my own games I have seen fewer advance Caro-Kann games (1. e4 c6 2. d4 d5 3. e5) than the semi-open games (3. Nc3 or 3. Nd2) or the Botvinnik systems (3. exd5 cxd5 4. c4 or 2. c4).
My questions are:

Has the advance Caro-Kann become less popular at club or master level?
How do we know? E.g. how can we mine a database to show opening popularity over time?

As for 2. Plot number of games played in a specific opening per month/year (or any other suitable time interval; such that you have a sufficient number of games in that interval.

@user1583209: True, but I'm asking more 'how to create that plot', i.e. which source would people use and how would the interrogate the data?

Not sure I understand your problem. You could take whatever general database with dates you have. (Want to avoid any databases that specialize in one opening only.)  Then you could use for instance pgn-extract to extract games by date (-Td flag) and ECO code (-TeB12) to give you games in the Caro-Kann advance variation for the specified year. (if there are no ECO code annotations in the database you could also match the position after the third white move)

Summary
From the plot of games played under the Caro-Kann ECO codes (B10-19), the advance variation (in B12, but B12 does hold some other miscellaneous variations) has been consistently the most popular line since the 1990's and peaked at 1,803 games in 2008.

Methodology

I extracted the games from the Fritz for Fun 13 into PGN format
I ran the following R code, which extracts the year (mandatory) and the ECO (optional). The games are filtered to ECO codes B10-19 (Caro-Kann) and for games from 1927. Why 1927? That is when it debuted at the top:

He [Capablanca] used it [the Caro-Kann] in his crushing strategic destruction of Aaron Nimzowitsch in the great New York tournament of 1927.

Source: The Caro-Kann: Move-by-Move by IM Lakdawala

The raw number of games are then plotted over time. Unfortunately my data only goes to 2009

library(ggplot2) # For making the charts look nice

dat <- readLines("C:/Users/Peter/SkyDrive/Chess/Fritz for fun 13 database.pgn") # Read in the data from a local file

eco <- dat[grep("\\[ECO ",dat)] # Extract the ECO, if there is one
eco <- sub("\\[ECO \"","",eco)
eco <- sub("\"\\]","",eco)

year <- dat[grep("\\[Date ",dat)]
year <- sub("\\[Date [\"]","",year)
year <- sub("\\..*","",year)
year <- as.numeric(year)

ecoindex <- grep("\\[ECO ",dat) # Find which lines have an eco
yearindex <- grep("\\[Date ",dat)
yearindex <- yearindex + 5 # The date is always the 3rd pgn tag and is mandatory. The ECO, if present, is the 8th tag
matchindex <- yearindex %in% ecoindex  # This code finds which games have both a year and eco tag

year <- year[matchindex] # Filter out games without an ECO

countgame <- table(eco,year)
countgame <- as.data.frame(countgame) # Convert to a data frame

Carocode <- paste("B",10:19,sep="") # ECO codes for the Caro-Kann are B10-B19

Carogame <- countgame[which(countgame$eco %in% Carocode),] # Keep the data for the Caro-Kann ECO codes

Carogame$year <- as.numeric(as.character(Carogame$year))
Carogame <- Carogame[Carogame$year>=1927,]

p1 <- ggplot(Carogame,aes(x=year,y=Freq,group=eco))+geom_line(aes(colour=eco)) # Plot count of games

p1 <- p1 + ggtitle("Number of Caro-Kann games over time") + ylab("Number of games")

print(p1)

paste0("B",10:19) is a tad simpler than paste("B",10:19,sep="") ;)

This advanced Caro-Kann is so tricky that few players have interest in this opening , This is much more complicated opening that sicilian dragon or the scotch game mieses variation also (i think).But it is playable , and it is recently also played in the game between  Veselin Topalov and Hikaru Nakamura (2016)london chess classics .But Topi lost in that game. http://www.chessgames.com/perl/chessgame?gid=1848832

e4 c6 2. d4 d5 3. e5 c5 4. dc5 Nc6 5. Nf3 Bg4 6. c3 e6 7. b4 a6 8. Nbd2 Ne5 9. Qa4 Nd7 10. Ne5 Ngf6 11. c4 a5 12. Nb3 ab4 13. Qb5 Be7 14. c6 bc6 15. Nc6 Qc7 16. f3 Bf5 17. Ne7 Rb8 18. Nf5 Rb5 19. Ng7 Ke7 20. cb5 Nc5 21. Bb2 Nb3 22. ab3 Qf4 23. Be2 Rc8 24. Rd1 Qg5 25. b6 Rc2 26. Bf6 Qf6 27. Nh5 Qc3 28. Kf1 Qe3 29. Re1 Qb6 30. Nf4 Qe3 31. g3 Qb3 32. Kg2 Kf8 33. Kh3 Qb2 34. Rb1 Qf6 35. Rhe1 e5 36. Nd5 Qe6 37. Kg2 Qd5 38. Rb4 Qd2 39. Rb8 Kg7 40. Kf1 Qh6 41. Kg2 e4 42. Rb3 Qe6 43. Re3 ef3 44. Kf3 Qh3 45. Rd1 Qh5 46. Kf2 Qh2 47. Kf3 Rc6 48. Rd4 Rg6 49. g4 Rf6 50. Ke4 Qh1 51. Kd3 Qb1 52. Kd2 Qb2 53. Kd3 Rc6 0-1
It is also reviewed by GM Daniel King - https://www.youtube.com/watch?v=UPQJWJcGbzg

As it stands, this doesn't answer the question. If the advance Caro is becoming less popular, then its complexity may be a reason why.


text:
How could I have extracted an opening advantage in this Owen's defence game?
I played as white against Owen's defence from black, which is seen as being quite dubious. After 21 moves, we agreed to a draw.
My question is, how could white have extracted an opening edge here?
[FEN ""]

1. d4 e6 2. e4 {2. c4 is also played in the Horwitz defence, but I wanted to aim for the French, as I used to play it as black} b6 3. Nf3 Bb7 4. Bd3 Nf6 5. Qe2 Bb4+ 6. c3 Be7 7. O-O h6 {This was the first move that surprised me, so I chose 8. Nbd2 and 9. Re2 simply because they were thematic, as I couldn't see a way to punish 7...h6} 8. Nbd2 d6 9. Re1 Nbd7 10. e5 {I'm not too sure about this move, but my plan was to make a few trades to play Nd2-f3 to liberate the dark square bishop. I also thought the open d-file could be useful} dxe5 11. Nxe5 Nxe5 12. dxe5 Nd5 13. Be4 c6 14. Nf3 a5 15. Rd1 Qc7 16. c4 Nb4 17. a3 Na6 18. Be3 c5 19. Bxb7 Qxb7 20. Rd3 O-O 21. Rad1  1/2-1/2

I'd say you DID get an opening advantage! Thanks to black's inaccurate play (5...Bb4+, 7...h6) you got easy development, control of the center, and no counterplay to worry about. What more do you want out of the opening?! It was more in the middlegame where your advantage started to slip.

Black's opening play doesn't look good. This is more passive and dubious than a normal Owen's.
The suggestion of 10. Nf1 followed by 11. Ng3 is a good one and should give white a nice advantage.
But I believe black should be punished harder for their passive play. Perhaps 8. e5 Nd5 9. a3!?.
[FEN ""]
[StartPly "17"]

1. d4 e6 2. e4 b6 3. Nf3 Bb7 4. Bd3 Nf6 5. Qe2 Bb4+ 6. c3 Be7 7. O-O h6 8. e5 Nd5 9. a3!?

Black has to worry about the knight on d5 getting trapped. After 9... c5 10. c4 Nc7 11. dxc5 bxc5 12. Nc3, white obtains a better position than they usually get in Owen's.
[FEN ""]
[StartPly "23"]

1. d4 e6 2. e4 b6 3. Nf3 Bb7 4. Bd3 Nf6 5. Qe2 Bb4+ 6. c3 Be7 7. O-O h6 8. e5 Nd5 9. a3!? c5 10. c4 Nc7 11. dxc5 bxc5 12. Nc3

Black's kingside looks really weak.

I really don't like 10. e5 which makes black's bishop on b7 strong, gives black an outpost for his knight on d5 and makes you lose control of the center. There is no need to force anything in the center. Instead of 10. e5 I'd consider regrouping your pieces, e.g. the knight from d2 could go via f1 to g3. Or you could try to create some weaknesses on the queenside by playing a4-a5. Or you could prepare a kingside attack playing h3 (which is useful even without kingside attack).

I do not believe that you should have agreed to a Draw after move 21)Rad1 since this is too early . If you compare the position of the Pieces White's pieces are ready for a K-side onslaught . The pawn is on e5 . I remember the great Alexander Alekhine stated that " When the pawn is on e5 White should attempt a K-side attack " . The Black Queen is somewhat misplaced and cannot come immediately to K-side for any rescue . Black has little to do on Q-side . From White Bf4,Nd2->Ne4 and then sac on f6 and then swinging Rook on g3 and Queen on h5 will definitely tie Black down . The Paws g4 h4 are also a part of White's arsenal .
One more thing : 10)e5 is just too early here . You could have delayed e5 for a moment and maneuvered Nf1 -> Ng3 .

Getting a substantial advantage in the opening against this type of system is very difficult in general, since Black's position is designed to cope with various direct attacking attempts from White. So the best course of action I'd reckon is to try and get a space advantage, and optimize your own piece placement. This is easier to accomplish, since Black isn't really trying to challenge White at all in the opening.
Consequently, I agree with user1583209 about the move 10.e5. This move is trying to clarify the situation in the centre by force, which is not in line with the approach of building up your position. You don't have to prove your advantage as White in the position after move 9; it's Black who has to prove equality!

If it seems like I've pointed out a lot here, well...this sort of thing is a problem for me too, knowing I have a space and development advantage I should be able to cash in but I don't. So I ran this through Fritz to see improvements. And you may like to do so, too. Sometimes it's frustrating to see a move that looks good but you don't quite have the guts/justification to play it.
Fritz gives 8. e5 Nd5 9. a3. It's always tough to know when to push the pawn, and while 8. Nbd2 looks natural, the Black knight is a target for the pawns, especially with the pawn on b6. It can't go to b5. So Black has to play ...Bg5 or ...g5 to protect it, each of which is ugly. ...c5 is a possibility, but dxc5 and Rd1 give you the open file.
With 8. Nbd2, an e5/a3 thrust leaves you open to Nf4. The thing is that while developing moves are good, the knight might be better placed on c3, and a3/c4 might gain space and give you that square. Also, if you are worried c3-c4 is wasting a move, remember that's not really the case. ...Bb4+ c3 Be7 provoked it.

Nxe5 also seems to relieve the pressure on Black. As a general principle you shouldn't exchange pieces when you have a space advantage unless you get something in return. But you still have an edge. Another poster noted the Bb7 could gain scope, but with a knight or bishop on e4, you are more likely to block it.
... c6 is also weak. It blocks the bishop, and c4! is vigorous. ...Nc7 is awkward, but ...Nf4 14. Qf3! loses a pawn. ...Nb4 15. a3 Na6 16. Qg4 and Black must play ...g5 or ...g6 with kingside pawn problems. White will again get the d-file. You played c4/a3 in the game, but letting Black get ...a5 in meant you found it tougher to play b4 and restrict Black's pieces on both sides of the board.

Finally, this is something I had to throw into an engine, but Rd3, while it doubles the rooks, also lets Black exchange them off. Fritz's idea of Nd2 followed by Qg4 and Ne4 looks strong. The point is that Black is too busy defeinding a kingside attack to swap rooks right away.

Bf4 also seems more accurate than Be3. It allows for an attack with Bc2 and Qd3 or e4. Black's having played ...h6 makes for a potentially weak kingside.

It looks like you considered the moves that a computer engine marked off as the best, and in some cases you played them a bit too late, and in some, a bit too soon. When you have more space it's tough to know when to squeeze and when to use tactics. Often you don't need to "just" develop with a space advantage. It may be better to restrict your opponent from meaningful development, for instance, with the early 8. e5. It's good to check for overextending, but Black's development isn't good enough to poke at any of your weaknesses.
The main problem for White is to figure how to take advantage of space and make Black's pieces stumble over each other. The Bb7 is rather good, but once Black plays ...c6 or ...c5 there are is that weakness on d6, and e4 is always available for a bishop or knight.


text:
What is the "stonewall formation"?
I use PyChess to play. It talks sometimes about how White or Black moved their pawns into "stonewall formation."
How do they do that, and what are the position's advantages/disadvantages?

Black usually reaches the Stonewall formation from the Dutch Defense (though QGD is an option as well, if he/she postpones Nf6) and involves putting pawns on c6, d5, e6 and f5. These pawns guarantee a strong grip on the light squares in the center (especially e4, which is often occupied by a knight later on), but weaken the dark squares. Another problem for Black is the light-squared bishop, which is severely limited by its own pawns. A typical Stonewall position is the following:
[FEN ""]

1. d4 f5 2. g3 Nf6 3. Bg2 e6 4. Nf3 Be7 5. O-O O-O 6. c4 d5 7. Nc3 c6

It's hard for White to crack Black's center, but he has many options, of which my favourite is to exchange some pieces and take advantage of Black's bad bishop in the late middlegame and endgame.
As @user1583209 notes, if White tries to reach this formation it's called the  Stonewall Attack – see the linked question for more details.

Just adding to the answer, there is an equivalent setup with reversed colors known as Stonewall attack where white puts his pawns on f4, e3, d4, c3. Much the same advantages/disadvantages apply to this as those mentioned above.

The stonewall setup results in Black putting their pawns on f5, e6, d5, and c6.  White could also play the setup by putting his pawns on c3, d4, e3, and f4.  In the rest of this post I will assume "Black" is the person playing the stonewall.
The Stonewall's idea is to close the center and gain attacking chances on the Kingside.  Due to its closed nature, the side playing the Stonewall has the opportunity to take their time developing and creating a plan.
The main drawback of the Stonewall is the big gap in the middle of the board on e5 created by the f5 and d5 pawns (assuming Black plays it).  This nuance usually gives White an advantage, as it is a very good outpost for one of the Knights.  This can be especially dangerous if White begins an attack on the Queenside, since the Knight on e5 is in a perfect position to target the c6 pawn.  If White pushes his b-pawn to b5 and has a Rook on the c-file, the c6 pawn will be under an unbearable amount of attack.  This is why it is vital for Black to begin his Kingside attack quickly, lest he be overwhelmed by White's positional advantages.
It's a dynamic opening that is a bit risky and slightly dubious, but if you play it right it can lead to some very exciting positions.
Here is a link to an article of two chess Grandmasters discussing the Stonewall setup:
https://www.chess.com/article/view/the-stone-wall
If you would like to look at some games that feature the Stonewall setup in them, here is a good link for that:
http://www.chessgames.com/perl/chesscollection?cid=1023312
For further information on the Stonewall, I would highly recommend looking up some videos of Grandmaster Simon Williams explaining it.  He's one of the world's foremost experts on the Stonewall and has written some very good books on it.
Hope that helps.

The one shown above is the more modern approach. The classic stonewall develops as f5/nf6/e6/d5/c6/Bd6 with Qe7/Qe8 ideas. White's Bg2 is biting on granite.
The stonewall is very simple to play strategically for Black. Most white players "scoff" at it when you play, but eventually, after they are tipping their king, learn to respect it.
It's fun.


text:
Could I have improved my position in this pawn up exchange Slav?
This game was my first correspondence game on chess.com.
I played as black. I felt my position was quite good. Then I grabbed a pawn and the game ended in a draw by threefold repetition.
My questions are:

How could black improve their game instead of playing 25...Rxe3?
Can you provide any other feedback to my game?

[FEN ""]
[White "mario401"]
[Black "Bad_Bishop"]
[StartPly "50"]

1. c4 c6 2. d4 d5 3. cxd5 cxd5 4. Nc3 Nf6 5. Bf4 Nc6 6. Nf3 a6 7. e3 Bg4 8. Be2 e6 9. h3 Bxf3 10. Bxf3 Bd6 11. Bxd6 Qxd6 12. O-O O-O 13. a3 Rac8 14. Be2 Na5 15. b4 Nc4? (15...Rxc3 {I played an 'auto-pilot' move and saw this tactic immediately afterwards,} 16. bxa5 Rxa3) 16. Bxc4 Rxc4 17. Na4 b6 18. Nb2 Rc3 19. Qd2 Ne4 20. Qe1 Rfc8 21. f3 Ng3 22. Rf2 h5 23. f4 h4 24. Na4 Rb3 {this was a crude attempt to trap the knight. Maybe I should have considered 24...R3c6 to maintain control of the c-file} 25. Qd1 Rxe3? {Only now do I realise that the rook can't go to e4 if attacked with 26. Qd2} 26. Qd2 Rb3 (26...Re4? 27. Nc3 f5 28. Nxe4 fxe4 {Black might look OK, having a protected passed pawn, but it is easily blockaded}) 27. Qd1 Re3 28. Qd2 Rb3 29. Qd1 Re3  1/2-1/2

Was this a correspondence game? To me it seems like you're not yet used to taking your time to hash out the critical variations. In correspondence chess you have the advantage of being able to move the pieces around, and you have plenty of time at your disposal to look at alternatives at every turn. That would be my biggest criticism of your (and your opponent's) play: neither of you seemed to be treating this as a correspondence game, and more like a rapid game.

@Scounged: definitely true. I played too fast most of the time. The time limit was 3 days per turn, and the whole game was wrapped up in 7.

Your play was good, and you managed to slowly gain the upper hand from the more or less dead equal opening.  At the end Rxe3 is forced, but after Qd2 I would have definitely considered Re4.  You actually don't lose the exchange:
25... Rxe3 26. Qd2 Re4 27. Nc3 Rc4!
Now at this point you're threatening to take on d4, so 28. Nxe4.  But then you take back on e4 with your g3 Knight and you have White's Queen and Rook in a fork.  You are winning back the exchange and are a pawn ahead.
Overall you played a good game.

+1 Thanks for your feedback and welcome to the site! Yes, I think in the final position I definitely had tunnel vision.

Thanks!  I joined a few days ago and I'm hoping to help answer questions wherever I can.  I have a chess.com account as well, so if you like we could play a few games once in a while.

25...Rxe3 appears to be forced. However, it's not a bad move, and you have several ways to keep an advantage afterwards. The simplest is 26...Nf5, just defending the rook and remaining up a pawn with a good position. After 26...Re4 27. Nc3 you could go for the forcing line 27...Rxc3 28. Qxc3 Ne2+ 29. Rxe2 Rxe2 30. Qc8+ Kh7 31. Qxa6 Rd2 when material is back to equal but black is doing well because of white's weak pawns and exposed king. Even this isn't necessary though, because 27. Nc3 isn't actually threatening anything: black's recapture ...Nxe4 will win back the exchange immediately, so you could also try to improve your position slowly, say with ...g6 and ...Kg7. I don't see much white can do about this. Overall, you thoroughly outplayed your opponent, but seemed to panic when something unexpected happened. You still had a great position!
As for other parts of the game, 24...Rc2 looks natural and good. Rooks on the 7th/2nd are usually great and this is no exception.

+1 good point about defending with 26...Nf5. I remember during the game saying to myself "the g3-knight is so well placed that it cannot move under any circumstances", unless of course, to defend against a simple threat :-)


text:
Is today's chess.com daily puzzle a draw (as hinted at in the puzzle title)?
Today's daily puzzle on chess.com is called Desperation Draw:
White to move
[FEN "r5k1/P4ppp/8/8/p1p1P3/4KP2/2P3PP/5R2 w - - 0 1"]

1. Rb1 Rf8 2. Rb8  *

One of the commentators asked:

What draw?

I agree with this. I think this is a simple win for white who threatens to promote soon when black has no counter play, e.g. 2...a3 3. Rxf8+ Kxf8 4. a8Q+ Ke7 5. Qxa3.
My question is, am I missing the draw in the position above?

Stockfish evaluates the final position as +67.5, after 2. ... a3 it is mate in 7.

No, you are not.
It's an easy win for white as far as I can see.

After solving the puzzle, I had the same thought: I didn't like the title (unless misdirection was part of the fun).  Then I wondered if it had to do with a different definition of draw than the chess definition - say, an American football play, or some such.  Then I decided I didn't care enough to do research.  :)


text:
How are the scores decided in Chess?
Consider the following pictures:

I would like to understand the following:

My understanding is that it depends on the opponent's move against our move. Am I right?
What is the minimum and maximum range of the score?
When one can achieve the maximum score at very first move?
What is the use of the score?

(Sorry for asking very basic questions. Newbie for the Chess stuff).

Those aren't scores; there are just three possible scores in chess: White wins, Black wins, and draw.
Those are evaluations of the chess engine; a score of +0.62 means the engine thinks White's position is better by 0.62 pawns. A negative score would mean Black is better. On professional level, a score of 1.5 pawns is in most positions decisive, i.e. enough to win the game. However, weak moves by the players will change the evaluation.
The maximum and minimum score depends on the chess engine you're using. If you play the game till checkmate, you will see that the scores will get larger (either more positive or more negative) until you see something like +#8 which means White can mate in 8 moves.

I'd say 1.5 pawns is usually decisive at an amateur level; at a professional level the cutoff is significantly lower than that.

@BlueRaja-DannyPflughoeft could be - but that's maybe a good topic for another question. I disagree; many endgames (especially rook endgames) are drawn despite one side being a pawn ahead and having a slightly better pawn structure/more active piece.

Being a pawn up is not equivalent to "a grandmaster/chess engine evaluating the position as having a pawn's worth of advantage".  A drawn endgame should be evaluated as 0.0, regardless of material inequality.

Yes, but endgames are chess engines' weak point (as long as they can't use tablebases). Like I said, a good topic for another question.

As pointed out by Glorfindel, these are evaluations, which tell you who the engine thinks is better. A positive score means white is better, a negative black is better and values around zero mean that both sides are equal. These evaluation values are (traditionally) displayed with two decimals which is much too high precision for humans. In practical play you would hardly notice a change of +-0.1 or so.
Take these values with a grain of salt, particularly for any evaluation between -1 and 1: there are many cases where the engine evaluations are not good, such as openings or closed positions with lots of maneuvering. Ignore the evaluation in these cases. On the other hand, in very tactical positions you can usually trust engine evaluations. Starting from values above around 1.5 (or below -1.5) in many positions the game ends decisive with a win for white (black) assuming perfect play.
The actual evaluation is calculated based on many factors. The main one is material, and this is also how the evaluation is normalized, namely such that a value of 1 corresponds to one pawn. Similarly other pieces have values of around 3 (bishop, knight), 5 (rook) and 9 (queen). Other factors include piece activity, king safety, control of the center, etc.
With regard to your questions:

What is the minimum and maximum range of the score?

In typical games you will find a maximum of maybe around 20 (or minimum of -20). Beyond that the engine can usually count down to mate and would display the number of moves to mate. If you wish you can probably construct a  very closed position (e.g. all pawns blocking each other) and give one player a huge material advantage and in that case you might be able to reach very large evaluation values where the mate is beyond the calculation power ("horizon") of the engine.

When one can achieve the maximum score at very first move?

There is no meaningful answer to this. If there is a first move which gives you maximum score this will depend on the details of the engine and the calculation depth more than on anything else. Another engine might very well give you another best first move. Engines are not powerful enough (or chess is too complex) to give you a good answer to this. That's why engines use opening books and do not calculate anything at the start of the game. Experience has shown that all  normal moves (1. e4,d4,c4, Nf3...) give white a small advantage but nothing more.

What is the use of the score?

For the engine, it decides what move to play based on this score. Very simplified you could say that the engine calculates all possible lines down to a certain number of moves and evaluates the final positions using this score. It then picks the line which gives it the best score in the final position.
For a human, you can use this score to analyze your own games or to analyze openings/endgames/... in order to find the correct moves or to locate blunders.

Although you do say that your description of how the score is used is simplified, one detail is worth mentioning: it doesn't pick the series of moves that gives the best possible score, since that would be a line in which the opponent makes a long series of blunders. It instead alternates: on its turn, it picks the move that yields the best score, and for the opponent's turn, it assumes they'll pick the move that gives the worst score (for it). Which is to say, it picks the series of moves that is optimal given perfect play by the opponent. more details

@Ray Agreed, that's what I meant.

Ok,
Going by your Questions I paste below and answer accordingly .

What is the use of the score?

The use is to determine whether you have an advantage or you are better playing or winning. For best results take a good game and analyse with Fritz/StockFish. You would see that as the game progresses there will be a shift as whoever plays well.

My understanding is that it depends on the opponent's move against our move.
  Am I right?

Almost true but not absolutely. The Score is a mathematical evaluation like for example during the start of the Game it is 0.0. It means both are equal at this point. The Score depends upon a number of factors like more space, pieces, king safety and a lot more.

What is the minimum and maximum range of the score?

The Score is always in favor of Black or White. You can see that when it has a winning combination it can be -infinity to +infinity. The higher the score it means it favors a particular side.

When one can achieve the maximum score at very first move?

It does not depend on you except you are playing your opponent at the beginner level and scholar's mate or fool's mate is played on board.


text:
The genders of the pieces and pawns
Historically, what, if any, are the genders of the pieces and pawns?  Is the king male and the queen female, etc?   What about promoted pieces?

All male. Even the queen was originally "The Advisor".

(possibly NSFW cartoon) https://i.warosu.org/data/tg/img/0301/23/1391974585894.png

Historically there was no queen. Check the history of chess, you will get the answer.

Chess originated in India and in the Indian armies of those times, it was common to have elephants, camels, horses and the like. Even now in rural India, the rook is the "elephant", the bishop is the "camel" and the knight is the "horse". The king is still the king, the queen is the "wazir" or vizier, and pawns are foot soldiers. In fact there was a recent Indian movie called Wazir, themed on chess and the Wazir was portrayed by a male character.
Traditionally, the armies fought mostly with men, however, even Indian history has had female warrior queens (for example Rani of Jhansi). The Wazir, however, is not a queen, but a powerful minister in the kingdom, maybe even the king's prime minister or right-hand-man (person?). Traditionally, this would be a male. Similarly, the elephant riders, camel riders, horse riders and foot soldiers would traditionally be male with females being the exception to the norm. The king is obviously male.

Yes, technically perfect answer.

Think about this. When pawns reach the other side they become Queens. Are the females? Or was this the first look on transgender people?

Logically, the pawns, Knights, Bishops, Rooks, and Queen are all female, but the King is male. This is why pawns can't promote into Kings.

@eyeballfrog i realised the 1st sentence a long time ago but not the 2nd sentence until now. WOW.

Depends on the language. E.g. Russian words for pawn and Rook are feminine. On the other hand, Russian words for (real life) infantry, cavalry, etc. are also feminine.

" Men are from Mars . Women are from Venus " . Quite an abstract Quote related to this Q . Isn't it ?
Ok why I say the above is because Chess originated as a game of war where there are two Kingdoms fighting against each other . In earlier days and even to this day a major portion you would see it is the men who always fights or takes part in Battle field compared to Women . True Women are somewhat competing with Men and showing good results but in medieval World this was almost prohibited .
So as Chess is as good as War so the Pieces/Pawns participating are all Males . In ancient Roman religion Mars was the god of war so men are categorised to fighting machines and that's the reason it implies the Gender is Male .


text:
Unable to understand why N.McDonald - A. Stromer (1991) is a draw and not a win
[Title "Black to move"]
[FEN "3k4/3r4/8/8/p7/8/4K3/1N6 w - - 0 1"]

1... 58. Kc7 59. Nc3

McDonald notes that if 59...a3, then "60 Nb5 wins it." I don't understand why this wins it. Can't the King just deflect the check and continue the game? Or by saying "... wins it", does McDonald mean that after that, the game is practically a win as he can mate easily?
If anything, I'd assume it'd just be another draw.  Can someone please clarify?

I suspect he means wins the pawn, as opposed to the game. A lone knight is insufficient material to mate, and black would have to cooperate to be mated with the rook vs. knight.

hmm, ok, that makes much more sense. Thank you!

This looks like a win for black. They should play Kc8, not Kc7, ans then they can bring the king up. White can never take the pawn as it will just move. If the knight moves onto the d-file,then the rook takes it and the pawn runs for a touchdown.
In the? position if black plays Kc7?, then white wins the pawn and the rook vs knight endgame would be tougher to win if at all.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
How to map file and rank to a square number in TSCP?
How can I map file and rank numbers (0-7) to a square number in Tom Kerrigan's Simple Chess Program?
I know how to do the conversion from square number to rank and file, but not the other way around.

I may help, but a little more details will be helpful. What part of the code in TSCP you have issues?

The conversions from square to row and column are defined in defs.h as:
#define ROW(x) (x >> 3)
#define COL(x) (x & 7)

so you can apply the inverse to generate the square number:
(row << 3) | col


text:
What is covered in "Grunfeld Defense: Russian Variations" (1988) by Eric Schiller?
I'm interested in the Russian system of the grunfeld-defense:
[FEN ""]
[StartPly "10"]

1. d4 Nf6 2. c4 g6 3. Nc3 d54. Nf3 Bg7 5. Qb3

I'd like to buy a book on this line alone (I'm not interested in books offering other mainlines, as I much prefer the Russian).
That's when I came across Grunfeld Defense: Russian Variations (1988) by Eric Schiller for sale on Amazon.
My problem is that I don't know what I'm buying, as there are no reviews, previews, blurb, contents or even number of pages for me to weigh up the benefits of purchasing.
So, my questions are:

What does the book cover?
Can you provide a review of the book?
Would you recommend any other resources specifically for the Russian system?

Eric Schiller has written very many books. I bought some of them. I was not impressed. But I am a weak player and I know very little about chess.

@bof Please elaborate on 'not impressed'? Was the knowledge unoriginal?

This is D96/D97 classification - ECO D would be your best bet. It would be comprehensive in variations but in Chess Informant style.
I would add this:
Even though Eric Schiller is somewhat known for his error-prone books, this book is in it's second edition. I would venture to say that, as far as Schiller books go, it might not be all that bad. It really depends on your playing level. If you are a relatively weak player (say, 1400 rating or less), I'm sure it is fine to get your feet wet using this book. It is important to know how not to play an opening as well as know how to play it. It might be a good jumping off point for the opening. Of course, get an inexpensive used copy if possible.
Good luck!

While I'm unfamiliar with the book, it was published in 1988.  A 29 year old opening book it obsolete and shouldn't be studied. There are more recent books on the Grunfeld that cover the Russian variation, albeit from the black side.  You could also search for chess videos on that variation.

Doesn't answer the question.

The original poster is interested in a particular opening variation and wanted to know if the book would be worth buying. The answer is that a 29 year old opening book is utterly obsolete and the purchase would be a waste of money and time.


text:
Could White have won this double rook endgame?
I reached this position as white that led to a draw:
[FEN ""]
[White "Bad_Bishop"]
[Black ""]
[StartPly "61"]
[Result "1/2-1/2"]

1. d4 d5 2. c4 dxc4 3. Nf3 Nf6 4. e3 Bg4 5. Bxc4 e6 6. h3 Bh5 7. Nc3 Nbd7 8. O-O Bd6 9. e4 e5 10. g4 Bg6 11. dxe5 Nxe5 12. Nxe5 Bxe5 13. f4 Qd4+ 14. Qxd4 Bxd4+ 15. Kh2 Bxc3 16. bxc3 Bxe4 17. g5 Bd5 18. Re1+ Kf8 19. Bb5 Ne4 20. c4 Nd6 21. cxd5 Nxb5 22. Rb1 a6 23. a4 Nc3 24. Rxb7 Nxd5 25. Re5 c6 26. Bb2 Rd8 27. Rf5 f6 28. gxf6 Nxf6 29. Bxf6 gxf6 30. Rxf6+ Ke8 31. Re6+ Kf8 32. Rxc6 Rg8 33. Rc2 Rg7 34. Rb6 Ra7 35. Rcc6 a5 36. Ra6 Rxa6 37. Rxa6 Rd5 38. Ra7 h5 39. Kg3 Rc5 40. Ra6 Kf7 41. Kh4 Ke7 42. Rh6 Rc4 43. Kg5 Rxa4 44. Rxh5 Ra1 45. Rh7+ Kd6 46. Ra7 a4 47. f5 a3 48. f6 a2 49. f7 Rg1+ 50. Kh6 Rf1 51. Rxa2 Ke6  1/2-1/2

I was up a pawn and had more active rooks. How could white have won this endgame (if there is a win at all)?

31. Kg3 to bring the king into the action must also be analysed.

48.Kf6 should be winning. After say 48...a2, white goes h4-h5-h6 and something involving ...Rh1, Rxa2 Rxh6+, Kg5 followed by Re2 will lead to the Lucena position.
Much earlier on, I believe 31.Kg3 is winning, but it's also the best try by elimination: without an active king (which is the most important non-trivial factor in rook endgames), white won't be able to win with just his f- and h- pawns vs. black's h-pawn if he loses his a-pawn, and after Rg8 as happened in the game, white's own king is exposed to a perpetual. Black is doomed to passivity because his rooks are disconnected, and white can slowly capture the rest of black's pawns and/or get his king to e6 and promote the f-pawn.
P/S: 17.Re1 Kf8 18.Ba3+ Kg8 19.Rad1 followed by 20.Re7 looks crushing.

Re1 0-0-0 and I see nothing for White.

I actually forgot black can castle, but I think after 18.g5 Bd5 19.gxf6 Bxc4 20.fxg7, white may have something.

I feel like you should have played 31. Rff7 or 32. Ree7 on the next move, doubling rooks on the seventh rank (even though I don't how much better it is :-) ). Black wouldn't have been able to create any play with his rook. Instead you (naturally) took the pawn freeing both black rooks.
Altogether I liked your game. GG!

"I think the position wasn't a draw until the move 48-49." After 44. Rxh5 you have only 7 men left and can therefore check with a tablebase which will tell you that it is a draw.

Upps... You're right. I wasn't aware of the fact that one tempo matters so much in that position. In fact if it was white's move again after 44. Rxh5, white would be winning. But "if..." :D (I should probably edit my post).

The original endgame might very well be a draw due to the open position and the large number of weak pawns.
The position after 45 .. Kd6? is won for white...until  48. f6?. You needed this square for the white king in order to escape from rook checks. Could have won with 48. h4.

Starting with 30 Rxf6 + Black to move Houdini 6.02 d = 39/81 takes to a winning seven pieces endgame for White (+ 2.53) . The endgame is even rook and three pawns vs rook. Mate in 30.

Stockfish 14.1 NNUE rules this endgame to be a clear win for White. It returns +6.30 after only 3 minutes of analysis. The key move is , after 30…Ke8 31 Ree7!! with a fatal bind for Black.

I meant …30 Ke8 31 Re6+ Kf8 32 Ree7!! with a fatal bind for Black.

You can edit your answer by the "Edit" button right below your answer.

Answer would benefit from an [edit] to correct the analysis.


text:
Which Book should I choose
After watching a good deal of annotated games of Mikhail Tal on YouTube, I've finally decided to go in deeper by the means of 3 of his most famous books

Life and Games of Mikhail Tal
Study Chess with Tal
Attack with Tal

Even after having bought all the three books, I don't know which one is the best...and sometimes the exercises become quite monotonous...what is your opinion?

What is your outcome? More importantly, what is your skill level? (Answer both questions.)

All the books??

What is your Chess ELO ?

It depends on what you are looking for.
Personally I like Attack with Mikhail Tal best because it is really an excellent textbook (or guide, see the introduction) on how to play attacking chess. So if you are looking to improve your own game, this is the book I would recommend.
If on the other hand you are more interested in Tal himself and his career, his personality and style, then you should definitely go for The Life and Games of Mikhail Tal, which has much more comprehensive coverage of those aspects.


text:
Is there a method or tip to best memorize current enemy pieces' movements?
I have started to play Chess again after a few years. It is not difficult to reproduce an opening or sticking with a plan during the middlegame, but the most difficult to me is to keep track of enemy pieces threats on open rows/diagonals/columns.
As an example during one game I've lost track of an open diagonal that has a bishop of the other player and no piece (white or black), and forget to take care of not letting pieces stay on that diagonal unprotected while I was thinking on something else (like a plan to stick with).
My question: Is there a tip or a known method of pros like "memorizing/imagine colors" or create a "mental X mark" inside all those squares that makes part of a enemy movement possibility?
Sometimes I get caught by those pieces that are full aggressive (not protecting anyone)...

What you are talking about is called "board vision". Googling "chess board vision" will get you a ton of stuff.
One thing that may help. On looking at an enemy piece (or one of your own) do not ask "where is it?" but ask directly "what is it doing?". For example, that Bishop is controlling that diagonal, which is annoying because I would like to use some of those squares. The battle for control of an important square might involve pieces close to or far away from that square, but they should be linked in your mind as participants in the same struggle. Psychologists call this chunking. You can remember things about a group of pieces more easily than about the individual pieces.

And searching for more information through the internet, i've got this - http://billwall.phpwebhosting.com/articles/chunking.htm - Chunking and Chess theories. This makes me wander, cause the best answer to my question would be a fusion o Your answer and @CConero 's answer...

Thats a good article. Let me try to give an analogy. Suppose you want to ask "Is there a nice outdoor park near here?" in a language that you don't speak very well. You have to recall the vocabulary word-by-word, and then the sentence structure and then put it all together. A fluent speaker just says it. I suspect they just make small modifications to a general-purpose
asking-directions chunk, because being able to ask directions is a useful skill. You know an amazing number of chunks. Here is a chess chunk. The Black pawns are on f7/g7/h6. It would be nice to put a White Knight on f5.

..Black can't easily drive it off with g6 without dropping h6, unless he prepares it with, say, Bf8. Awareness of this typical chunk may explain why White would play Nd2 because  that gives him a route to f5 via f1 and g3. It would also explain why Black might play Re8 because that prepares Bf8. Both players are aware of a potential chunk that a beginner might not notice. They are thinking of adaptable patterns. Experience makes this easier as you learn what chunks are useful. This is how you use vision and develop vision. But basic internet vision exercises that train the eye are needed too.

I would think that with regular play, your "sight" of the board will improve.  It's like anything else in that practice will lead to improvement.  Also, playing a lot will enhance your sense of where things are on the board.  For example, in a fianchettoed position, you'll automatically sense that the enemy bishop is on the long diagonal. At least I've found those things to be true for myself, and I would think that they'd apply universally.

And playing is the only way to improve it? There is no other way i could make my brain "see" and keep that on short memory during a chess game?

Doing tactics problems regularly should help with this.  There are numerous sites where you can do that, such as ChessTempo and Chess.com.  One wit said that tactics are 99% of chess, maybe an exaggeration, yet with a grain of truth. And playing regularly will help with your pattern recognition by seeing a lot of positions. Then when a favorable one reappears, you'll recognize it.

As I said below, the problem here is to choose an answer, since yours and @PhilipRoe's should be merged to create the best one :)

My question: Is there a tip or a known method of pros like "memorizing/imagine colors" or create a "mental X mark" inside all those squares that makes part of a enemy movement possibility?
So, you are asking about visualization exercises. Link below:
CVT
Helpful exercises for 'knowing' the chessboard.
Also, you probably need tactical training too. There are many sites for that and every server has exercises to test yourself.


text:
How do I respond to 8. g3?! in the 4. e3 Slav?
This is taken from a rapid game where my opponent threw me by playing 8. g3, coming out of book in the 4. e3 Slav:
[FEN ""]
[StartPly "17"]

  1. Nf3            Nf6
  2. c4             c6
  3. d4             d5
  4. e3             Bf5
  5. Nc3            e6
  6. Nh4            Bg6
  7. Nxg6           hxg6
  8. g3

I didn't keep a gamescore (it was at work during a lunch break), but I remember at this point I could think of no constructive plan at all (I played 8...Bb4 and ended up playing 2 knights vs. 2 bishops with a cramped game).
My question is, what should black have played on move 8 and why?

I see no reason to ?! mark. 8. g3 is good book move and standard way to limit opponent's play with open h-file. The most flexible move by far is 8...Nbd7 after it. After 9.Bg2 dxc4 should be good. But again, 4...Bf5 is no refutation of slow Slav and 5...Bg6 is in my opinion less challenging than 5...Be4, while there's nothing wrong with 8.g3. Don't expect you have guaranteed equality in this line. Once I played the NN vs. BB game in similar line and it is suffer, even if computer says it is OK. I was always somewhat worried about 4...Bf5 as white, but as black, I played 4...Bg4 every single time :-)

Thanks. My book didn't cover g3 at all, which is why it threw me I think.

There is nothing to worry about when an opponent makes a surprise move in the opening and you are unaware of it.
g3 is not a move that you would be blown away by it. Just follow basics to develop your pieces. Black has the open h-file. Nbd7 and then a centre break of e5 should follow next course. The bishop on f8 comes to b4 or d6 and knight comes to e4. I think black has a better piece activity and should have gone on to winning the game.