Question

It is known to us that it takes years of ______ practice to gain ______ skills of ______ expert.

[　　]

A．/; the; an

B．/; the; the

C．the; the; an

D．a; /; the

Answer 1

答案：A
解析：

practice 不可数名词，表泛指，不用冠词；skills of... 表特指，前用the；“一个专家的技能”，expert 前应该用an。