Great changes have taken place in that school．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

答案及解析： A

此题考察连词的用法。

第一空what引导表语从句，what在表语从句中作表语。

第二空when引导定语从句，先行词是20 years ago。本题较难。What引导表语从句，what在从句中作主语、宾语或表语；that也可引导表语从句,但不作成分，不能省略且无词义。

①Is this what you want to tell me?（what引导表语从句，同时又作tell的宾语）

②The problem is that we have not enough money to buy the expensive car．（that引导表语从句，但不作成分）