Great changes have taken place in that factory. It is no longer it was 20 years ago it

问题补充：

Great changes have taken place in that factory. It is no longer

it was 20 years ago, it was so poorly equipped.

A. what ,when

B. that ,which

C. what ,which

D. which ,that

答案：

(答案→)A. what ,when

B. that ,which

C. what ,which

D. which ,that

解析：因为it was 20 years ago中缺少表语，所以第一空应该填what引导表语从句。第二空which引导定语从句，which代替前面整句话的意思，故答案A。