介词宾语从句中what 与that用法区别

问题描述:

介词宾语从句中what 与that用法区别
介词加what或that的用法
The money spent on food was just one fourth of____spent on education.A that B what C which D the one
为什么不能选B that 与what 在介词宾语从句中怎样区别使用

这句话不是介词宾语从句,这是一个比较状语从句,是拿花在food上面的钱和花在edu上面的钱比较.后面用代词that指代前面的money.
就算是理解成介词of后面接的一个宾语从句what做主语,你也不能直接说what spent on education,而是应该说what was spent on education因为后面宾语从句要完整,钱是被花在教育上,被动语态要有be动词,所以也不会选what