what 引导主语从句时应注意其所指的具体内容来确定谓语的单复数 为什么 what做主语时谓语不就用单数吗

Question

具体解释 谢谢 What we need is more time ,while what they need are more doctors and medicines

Answer 1

不一定，从句通常可以看做“一件抽象的事”，进而可以用it形式主语

但是有些主语从句，在具体的语境下并不抽象，而是可推知的“具体的物”,可以单 也可以复

比如：What he picked up are some books.
What he picked up is a book.

但是抽象涵义时，只能是单数，如：
What students pick up in this course is gonna changes their lives.追问

抽象涵义时，只能是单数 具体意义时具体的物如果是复数谓语就用复数 如果是单数谓语就要用单数？？？ 可以这样说吧

追答

嗯 是的 通常你的答案能够说服自己的时候，也能够说服别人
另外一个答案 从另一方面讲也是对的
what/ how本身就是复合关系词，等同于“先行词+关系代词”，所以不能引导定语从句
What we demand most is time. Time is all that we demand most.
Tell me what’s happening. Tell me something that is happening.
I don’t like how you behave. I don’t know the way (that/ in which) you behave.

来自：求助得到的回答

Answer 2

What we need are more books.--->what =the things which----> the things are more books. 其中的we need 只是主语what的定语从句，故在本句中用复数的are.
What we need is more time 句中的what=the thing which，故本句主语的单数意义，用单数的is