When using 是...的, what should I do when there is both a direct and an indirect object (e.g. 这样话是我告诉他的) or a separable verb (e.g. 这本书是我读书的)? I'm having difficulty around the position of two kinds of objects in the 是...的 structure.
First, what should I do when there is both a direct and an indirect object? Would &quot;这样话是我告诉他的&quot; be correct?
Secondly, what should I do when there is a separable verb? Would &quot;这本书是我读书的&quot; be correct?
A 是 B C 的
“A 是 B C 的” is an emphasized version of &quot;B C A&quot;.

A: object
B: subject
C: verb

The emphasis is on B, that subject B is responsible for action C. It very likely that action C is complete and has some visible effect. A can be omitted sometimes if not important.
It can usually be translated into &quot;It is B that Ced A.&quot;
这饭是我做的. 
It is I that cooked the meal. (not Tom, not Jerry.)

A: 这是谁干的?
A: WHO did this?
B: 是我干的。
B: It is I did it. (I take full responsibility.)

In your example, &quot;这样话是我告诉他的&quot;, is correct in structure, but “这样” should be “这”
这话是我告诉他的。
It is I who told him so. (there are no other people that told him this)

&quot;这本书是我读书的&quot; is not correct. First. It should be &quot;读&quot; instead of &quot;读书&quot;. Because if you put it back into original (not emphasized) order, it will be &quot;我读书这本书&quot;, where &quot;书&quot; is repeated.
However, you cannot say &quot;这本书是我读的&quot; because the effect is not directly visible, and there is no point to emphasis.

A 是 B D C 的
&quot;A 是 B D C 的&quot; can be translated into &quot;It is D that B Ced A&quot;

A: object
B: subject
C: verb
D: adverb

&quot;这本书是我最近读的&quot; is a correct sentence. The decoration gives some additional information, so there is something to emphasize: the emphasis is on &quot;最近&quot;. It can be translated as It is recently that I read the book. (not a long time ago)
&quot;这话是我昨天告诉他的。
It is yesterday that I told him this information. (not today, not the day before yesterday.)