My father bought me several books,but________was interesting.

题目

My father bought me several books,but________was interesting.
A.all of which B.none of them C.none of which D.all of them
为什么用none of them?
和下面这句有什么区别?
The old man has two sons,________are lawyers.
填的是 both of whom

答案

关键的是连词but第一句有连词,所以后面也应该是一句完整的话none of them was interesting而第二句不是连词连接的,而是要使用从句whom就要指代two sons了要是这句是The old man has two sons,but ________are lawyer...