定语从句

定语从句。
一个用来修饰名词或代词的句子叫定语从句。例如：
The man who told you the news is a friend of mine.
定语从句是由关系代词和关系副词来引导的。关系代词有：who, whom, whose, which, that. 关系副词有：when, where, why 等。
1.who代替人，在从句中做主语。
Do you know the man who wrote the article?
What was the name of the man who danced with you last night?
2.whom代替人，在从句中做宾语
This is the boy whom we were looking for .
3.whose代替人，在从句中做定语
What is the name of the student whose father works in our lab?
The building whose roof we can see from here is our department.
4.which代替 物，在从句中做主语或宾语
That was a fault which could be forgiven.
I will use the reference book which you borrowed from library。
5.that代替人或 物，在从句中做主语或宾语
Who is the man that is lecturing in the classroom.
Who is the man that talked with you?
6.when表示时间，在从句中做状语。
We don’t know the exact time when we needed help.
The day will come when we will win the final victory.
7.where.表示地点，在从句中做状语
The house where we used to live has been pulled down.
8.why表示原因，在从句中做状语
Do you know the reason why he was so happy?
定语从句when, where 相当于“介词+which
This is the room in which chairman Mao lived.
I will never forget the day on which I became a Party member.
注意：
1.动词+关系代词引出的定语从句
The man to whom you are talking to is the manager of the company.
The world in which we live is made of matter.
The famous professor of whom we nave often heard will come to our university .
2.名词+介词+关系代词引出的定语从句
There are nine planets in the solar system, some of which are much larger than our earth.
There are some new terms in the article, the meaning of which may be difficult to the students.
定语从句又分为两种：限制性定语从句和非限制性定语从句。注意这两种定语从句之间的区别。限制性定语录从句与先行词之间的关系密切，一旦去掉从句，主句意思不完整，甚至在逻辑上不能成立。这种从句和主句之间一般不能用逗号分开。例如：
She has a son who is a doctor.
这类从句译成中文时，要把从句译至先行词之前。“她有一位当医生的儿子”。
非限制性定语从句与先行词之间关系不密切，只是对先行词作些附加说明。本身也具有独立性。如果从句去掉，主句的意思仍然完整。从句与主句之间常用逗号隔开。在非限制性定语从句和主句之间不用that,只能用which.