I’ve read all the books were borrowed from the library.为什么填THAT WHICH 也可修饰物 也可做主语?

问题描述:

I’ve read all the books were borrowed from the library.为什么填THAT WHICH 也可修饰物 也可做主语?
为什么不用WHICH?

因为先行词books的前面有all修饰,出现这种情况,关系词只能用that