which和that的区别：引导非限制性定语从句时，通常要用which。直接放在介词后作宾语时，通常要用which。当先行词有the very，the only，the same等修饰时，通常用that。当先行词有形容词最高级或序数词等修饰时，通常用that。
which和that的区别
指代不同
1、which：哪一些。
2、that：那个。
侧重点不同
1、which：非限制性定语从句中关系代词一般要用which。
2、that：先行词是all、anything、everything、nothing等，关系代词应用that。
which造句
1、Which one do you like best?
你最喜欢哪一个？
2、Which period of history would you most like to have lived in?
你最喜欢生活在哪一个历史时期？
3、You must signal which way you are going to turn.
你要朝哪个方向转，必须发出信号。
that造句
1、She of all people should know the answer to that.
在所有的人中，唯有她最应知道那个问题的答案。
2、I'd like to come on to that question later.
我想以后再讨论那个问题。
3、I've told you time after time not to do that.
我一再告诉过你不要干那件事。