What is the meaning of 喜欢是喜欢? In the following sentence:


  保龄球我喜欢是喜欢，不过打得不好。


Why does this sentence use two 喜欢 and what is the verb in this sentence? 

I understand that "the speaker likes bowling" and "the speaker nonetheless are bad at bowling". But I don't understand how 喜欢是喜欢 works grammartically...
喜欢= like to; love to

欢喜= happy


  
  保龄球我喜欢是喜欢，不过打得不好-- (As for bowling, It is true that I like it, but I am not very good at it.)
  


[Subject XX 是 XX]= [granted/ It is true that subject is XX] 

Example:

"他贪心是贪心, 但他不会为了钱做违法的事情"= "他贪心是真的, 但他不会为了钱做违法的事情" (It is true that he is greedy, but he wouldn't do any illegal thing for money)


  
  能夠打保龄我是很欢喜，但我必须先完成作业-- (I am very happy for able to go bowling but I must finish my homework first.)