继续来点专业知识

只用that不用which的情况

1、先行词为 all , much, everything, nothing , something ,anything, nothing, none, the one等不定代词时。

eg. This is all that I need.这就是我需要的东西。

2、先行词被the only，any, few, little, no , all, just , the very ,right等修饰时。

eg. I have finished reading all the books that I borrowed from the library. 我己经看完了所有从图书馆借来的书。

3、当先行词是最高级或被形容词最高级修饰时。

eg. This is the best that can be done now.这是现在能做的最好的办法。

4、当先行词是序数词或被序数词修饰时。

eg. This is the first book that I bought in the shop . 这是我在这家书店买的第一本书。

5、当先行词既指人又指物时。

eg. We talked of things and persons that we remembered. 我们谈起了我们记住的人和事儿。

6、如有两个定语从句，其中一个关系代词已用which，另一个关系代词则宜用 that。

eg. Which is the book that you bought yesterday? 哪一本书是你昨天买的？

7、主句是There be结构,修饰其主语的定语从句宜用that 作关系代词。

eg. There’s still a room that is free.还有一个空房间。

8、被修饰成分为表语,或者关系代词本身是定语从句的表语时，该关系代词宜用that。

eg. Our school is no longer the school that it was ten years ago .我们学校已经不再是十年前的样子。

9、有时为了避免重复而使用that引导定语从句。

eg. Who is the man that you spoke to just now? 刚才和你说话的那个人是谁？

只用which不用that的情况

1、 当介词放在关系代词之前时。

eg. This is the house in which I once lived. 这是我曾经居住过的房子。

2、 在非限制性定语从句中。

eg. Peter, whom you met in London, is now back in Paris.彼得现在回巴黎了，你在伦敦见过他。

3、 当关系代词指整个主句的概念时。

eg. He said the girl was too fat,which made her very angry.他说这个女孩太胖了，这让女孩非常生气。

只用who不用that的情况

1、当先行词是one, ones,anyone或those时。

eg. God helps those who help themselves. 上帝帮助那些能够自己帮助自己的人。

2、当先行词是序数词或被序数词修饰时

eg. They were the first who were there. 他们是去那里的第一批人。

3、当先行词是人，后面有较长修饰语时。

eg. Do you know the student in white with books in his hand who is standing under the tree?你认识那个站在树底下穿白衣服手里拿着书的学生吗？

4、当先行词与定语从句被其他句子成分隔开时。

eg. He is the only doctor in this hospital who I trust. 他是这家医院里我唯一信得过的医生。

5、当先行词是I,you,he,they等时（常用于谚语中）。

eg. He who doesn’t reach the Great Wall is not a true man.不到长城非好汉。

6、先行词是指成员的集体名词。

eg. People who are more confident are more likely to be successful.比较自信的人更有可能成功。

7、who可以引导非限制性定语从句。

eg.  Mr Green, who is a great teacher, is popular among students.格林先生在学生当中很受欢迎，他是个不错的老师。

8、当表示人的先行词由两个定语从句重叠修饰时(即双重定语从句)，第二个定语从句只能用who/whom引导，而不能用that。而且第二个定语从句的引导词不能被省略。

eg. The only person I know who has a skeleton in the cupboard is George Carlton. 我所认识的唯一的在柜中藏骷嵝的人便是乔治. 卡尔顿。

9、There be结构中，主语是人时。

eg. There is a girl who is waiting for you.有个女孩在等你。