定语从句中用which不用that引导定语从句的三种情况:
①非限制性定语从句用which,不用that引导。
如: Football,which is a very interesting game,is played all over the world.
He changed his mind, which made me angry. 
She is an artist,which I am not. 
②先行词为that时,为了避免重 复,定语从句用which不用that引导。
如: That which you borrowed from me wasn't a real diamond necklace.
Let me show you the novel that I borrowed from the library which was newly open to us. 
③介词后用which不用that引导。
如: The method with which you solved the problem is very good.
This is the one of which I'm speaking./This is the one I'm speaking of.
Bejing is the place in which i was born
定语从句不能用that的三种情况
1、 在非限定性定语从句中不使用 that,而要用 which:I have read all the books, which were assigned by the professor last week.
2、 在由介词引导的定语从句中不使用 that,而要用 which/what(指代物),或 whom(指代人):
I have read all the books, three of which were assigned by the professor last week.
I could tell the difference, among whom I used to work with.
3,which还可以用作关系限定词,后跟名词,that则不能这样用。例:
He changed his mind for the second time, after which I refused ever to go out with him again.
他第二次变卦,以后我再也不跟他出去了。