定语从句的关系词用法
一.关系代词who (whom)的用法
who可以代人(即它的先行词必须是人)，在从句中可以担任主语，往往也可以代替在句子中担任宾语的whom，但它的前面不能有介词，如果带介词则必须用宾格的
whom：介词+whom
例：This is the teacher who teaches us maths.这就是教我们数学的老师。
在从句中作主语
She is the girl who (whom) I met at the party.她就是我在晚会上认识的那个女孩。
在从句中作宾语(who可代替whom)
She is the girl with whom I went there.她就是和我一起去那儿的女孩。
在从句中作介词with的宾语
二.什么情况下宜用who，而不用that.
1.先行词是one ones anyone时宜用who
例：The ones who flatter me don’t please me.那些奉承我的人并不能取悦于我。
Anyone who fails to finish the task given should be criticized.任何人不能完成指定的任务，都应受到批评。
2.先行词为those时，宜用who为关系代词。
例：Those who want to go to the Great Wall sign up here.凡是想去长城的人在这里签名。
3.当先行词有较长的后置定语时。
例：I met a foreigner in the street yesterday who could asked me questions in Chinese.昨天，在街上，我遇到了一位能用汉语问我问题的外国人。
4.一个句子中带有两个定语从句，其中一个定语从句的关系代词是that，另一个宜用who。
例：The boy that you met last night is the group leader who studies very hard.昨天晚上你遇见的`那位男孩是位学习非常努力的组长。
5.在there be开头的句子中。
例：There is an old man who want to see you.有位老人要见你。
三.关系代词whose的用法。
例：whose是代词的所有格，它既可以代人也可以代物。
I saw a woman whose bag was stolen.我看见了一个皮包被偷了的妇女。
Please show me the book whose cover is red.请把封面是红色的那本书拿给我看看。
四.关系代词that的用法。
1.首先要特别注意只能用在限定性定语从句中，在非限定性定语从句中永远不能用that，另外介词后面不能跟that，而跟which。
例：Mike’s dog，which was very old now，became ill and died.麦克的狗，已经很老了，病死了。
2.在限定性定语从句中that和which在代替物时，一般可以通用。
例：The money that(which)my mother gave me yesterday has been stolen.昨天我妈妈给我的钱已经被偷走了。
3.在以下这些情况下，只宜用that，而不用which。
1) 先行词是最高级形容词或者它的前面有最高级形容词时。
例：This is the best that has been used against pollution.这是用来防止污染的最好的办法。
2) 先行词是序数词时，或它的前面有一个序数词时。
例：He is the last person (that) I want to see.他是我最不想见的人。
3) 主句已有疑问词who或which时。
例：Which is the bike that you lost?你丢失的是那辆自行车?
4)先行词既有人又有物，宜用that。
例：Do you know the things and persons that they are talking about?你知道他们正在谈论的人和事情吗?
5)先行词是all much little something everything anything nothing none the one 等代词时。
例：You should hand in all that you have.你应该把你所拥有的一切都交上来。
I nean the one that you talked about just now.我指的是你刚刚谈到的那个。
6)先行词前面only any few little no all one of the same 等词修饰时。
例：The only thing that we can do is to give you some money.我们唯一能够做的就是给你一些钱。
Li Ming is one of the students that want to be teachers in our class.李明是我们班想当老师的学生之一。
7)有两个定语从句，其中一个关系代词已用which，另外一个宜用that。
例：Edison built up a factory which produced things that had never been seen before.爱迪生办了一个工厂，生产过去从未见到过的东西。
五.关系代词which的用法。
1.在非限定性定语从句中，只宜用which，不能用that。
例：Beijing，which is the capital of China，is a very beautiful city.北京是中国的首都，它是一座美丽的城市。
2.在限定性定语从句中和在代物时常常可以通用，但有时只宜用which，不用that。
1) 关系代词前有介词时。
例：This is the hotel in which you will stay.这就是你将要住在那里的旅馆。
2) 如果有两个定语从句，其中一句的关系词是that，另一个宜用which。
例：Let me show you the novel that I borrowed from the library which was newly open to us.让我给你看看我从新开放的图书馆借来的小说。
