返回目录：ppt怎么做
定语从句
一，定义：修饰一个名词或代词的从句称为定语从句。
二，构成：
先行词+关系词+句子（不完整，需要将关系词所代替的先行词放到句子中才完整）
1，先行词：被定语从句修饰的名词或代词称为先行词
2，关系词：引导定语从句的关联词称为关系词
1）关系词有关系代词和关系副词
关系代词：who, whom, whose, which, that, as等
关系副词：where, when, why等
关系词 | 指代人或物 | 定语从句中充当的成分 | |
关系代词 | that | 人或物 | 主语、宾语、表语 |
which | 物或主句内容 | 主语、宾语或定语 | |
who | 人 | 主语或宾语 | |
whom | 人 | 宾语 | |
whose | 人或物 | 定语 | |
as | 人或物或主句内容 | 主语或宾语 | |
关系副词 | when | 时间 | 状语 |
where | 地点 | 状语 | |
why | 原因 | 状语 |
2）关系词常有三个作用：a,引导定语从句；b,代替先行词；c,在定语从句中充当一个成分
Harry Potter is the most interesting novel that I have read.
that I have read是定语从句；novel是先行词；that 是关系代词，代替先行词novel，在从句中作have read的宾语。
三，限制性定语从句和非限制性定语从句
限制性定语从句形式上不用逗号和主句隔开，是先行词不可缺少的部分，去掉它主句意思往往不明确，翻译成先行词的定语，“……的……”
His brother who is now a lawyer always encourages him to go to college.
非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开，通常翻译成主句的并列句
关系代词指物时不能用that，只能用which
.His brother, who is now a lawyer, always encourages him to go to college.
I don’t like the bike,which was bought last year.
四，关系代词的用法
1，先行词是人用that ，who ，whom(做宾语）
She is the woman (whom / that/who) I wanted to see yesterday.
Who is the man that /who is standing there?
2,先行词是物用that, which
This is the very dictionary that/which I want to buy.
I don’t like the book that/which you bought for me yesterday.
3,先行词在从句中作定语用whose(不管是人还是物。另外，所修饰中心词要一起提到从句的句首。)
The classroom whose door is broken is ours.
I know the man whose article I read yesterday.
4，定语从句也可以修饰整个句子，或句子的一部分，用逗号隔开在句后或句首，关系代词用which/as, 当从句在句首时，只能用as。
They have invited me to visit their country, which/as is very kind of them.
The activity was postponed, which/as was exactly what we wanted.
As you said, he is a very good student.
As you know ,we won the competition.
5,当关系代词所代替的先行词，在定语从句中它的前面有介词时，常常将这个介词也提到关系代词的前面。
I don't like the school in which we used to study .
I don't like the school which we used to study in.
The tool with which he is working is called an eraser.
The tool which /that he is working with is called an eraser.
6,关系代词所代替的先行词在从句中做宾语并且前面无介词时，可以将关系代词省略。
He is the man (that/who/whom) you have been looking for.
I want to read the book ( that ) you read yesterday.
五，关系副词的用法
关系副词是由关系代词转化而来。
当介词加关系代词表是在什么时候的时候，可以用when代替。
当介词加关系代词，表示在哪里的时候,可以用 where代替。
当戒指加关系代词，表示为什么的时候，可以用why代替。
when, where, why 就是关系副词,在定语从句中作状语。
I will never forget the place(in which)where we lived together.
The house(in which)where there are many books is the library.
I always remember the day(on which )when the accident happened.
The days(in which)when we traveled in Shanghai were pleasant.
The reason (for which）why he is late today is to get up late.