主要分两种比较： 1、which和that：which指代物,还可以指代一句话（I want to take away the book which you showed me yesterday我想带走你昨天给我看的那本书.He lost his way,which delayed him considerably他迷了路,这使他耽搁了很久.）. that不能指代一句话,不能用于非限制性定语从句等等区别.它们的区别你可以看看一些语法书的. 2、which、who和whom：who和whom只能指代人只是whom只能是从句的宾语,I know the girl who wears a red coat.That is the man about whom we were speaking)
