This is the ring on which she spent 1000 dollars.

题目

This is the ring on which she spent 1000 dollars.
为什么which前加on?为何这么用?

答案

on which 可以替换成what,on 添加到最后
spent on 是一个词组,宾语从句主语是which时on提前就是on which,同样还有in which at which