Playing basketball is sometimes very tiring I enjoy it very much.A. soB. butC. ifD. or

问题补充：

Playing basketball is sometimes very tiring, I enjoy it very much.

A. so

B. but

C. if

D. or

答案：

A. so

(答案→)B. but

C. if

D. or

解析：句意：打篮球有时非常累，但是我非常喜欢。so所以，but但是，if是否、如果，or或者。tiring和enjoy it very much是两个相反的意思，故选B.