Question

What we need ___(be) good books怎么填

Answer 1

我认为是填are

白勇语法中提到：what引导主语从句的主谓一致
1）what在从句中充当主语时，从句谓语动词一般与主句谓语动词相一致
2）what在从句中充当宾语时，主句谓语动词由主句谓语动词后的名词决定
（本句中，what是宾语）

what引导的主语从句，谓语动词一般用is。
但是有这样几种例外：
1. 如果主句补语是复数名词，则动词用复数：（我们需要的，书应该是主句的补语吧？就是这种情况）
What was real to him were the details of his life.
2. what分句本身明显表示复数意义, 比如what分句的动词和补语都是复数，那么主句动词也用复数，例如：
What are often regarded as poisonous fungi are in fact edible.
再比如 what 是限定成分，其后带复数名词，那么主句动词也用复数，例如：
What ideas he has are his wife's.

Answer 2

is
主语从句

追问

为什么不填are

追答

写错了 是are
What 引导主语从句时,主句谓语动词的单复数由表语的单复数决定. 如：
What he wants are these books.
What he wants is some water.

Answer 3

用is, need 怎么复数？