根据定语从句与先行词之间关系的紧密程度，我们将定语从句分为限制性定语从句和非限制性定语从句。

限制性定语从句

一、特点

最明显的特点：从句和主句的关系紧密，中间不用逗号隔开；

关系代词: that, which, who, whom, whose，as；

关系副词: where, when, why

定语从句是先行词在意义上不可缺少的定语，如果去掉，主句意思就不完整。

The woman who/that survived the earthquake is Amy’s English teacher.

This is the man ( who/ whom/that ) the police have been searching for.

I live next door to a couple whose children often make a lot of noise.

非限制性定语从句

一、特点

从句和主句之间用逗号隔开。

关系代词: which, who, whom, whose, as

关系副词: where, when,（注意，没有why）

②从句和主句关系不紧密，去掉从句，主句意思仍完整。

My new car, which I paid several pounds for, is not running. (which 指代先行词my new car)

He is English, which I know from his accent. (which指代整个主句的内容)

二、引导词的使用

(1)非限制性定语从句不用that引导

非限制性定语从句的关系代词无论指“物”还是指“人”，都不能用that。指人时，如果关系代词在从句中作主语，则用who, 作宾语则用whom; 指物时要用which。关系代词在从句中作宾语也不能省略。

Holly, who is from Australia, has a good command of Chinese.。

The book , which my mother bought for me yesterday ,is very interesting.

(2)关系代词和关系副词的选择

关系词在从句中作主语或宾语时，用关系代词; 在从句中作状语时，用关系副词。

The old man has a daughter, who is an artist.  (who 在从句中作主语)

Opposite is St. Paul’s Cathedral，where you can hear some lovely music.  (where在从向中作地点状语)

限制性定语从句与非限制性定语从句的区别

My elder sister who has settled in Beijing sends me an e-mail almost every day.我已在北京定居的姐姐几乎每天都给我发一封电子邮件。(限制性定语从句，意思是“我”可能还有其他姐姐)

My elder sister, who has settled in Beijing, sends me an e-mail almost every day.我姐姐已在北京定居，她几乎每天都给我发一封电子邮件。(非限制性定语从句，言外之意是“我”只有一个姐姐)

He is the man who has been removed from the company.  他就是那个被公司开除的人。(限制性定语从句)

The project, which lasted three years, cost no less than 1 billion dollars. 这个工程历时3年，耗资多达10亿美元。(非限制性定语从句)

(3)先行词不同

This is the best novel that I have ever read.  (限制性定语从句，先行词是the best novel)

The novel, which I read last night, is very interesting.  (非限制性定语从句，先行词是the novel)

She said she had finished her work, which I doubted very much.  她说她已经完成了工作，对此我深感怀疑。(非限制性定语从句，先行词是整个主句)

(4)关系词的使用情况不同

①that, why不能引导非限制性定语从句，要用which/ who/whom代替that,  用for which代替why。

Most people didn’t vote for him, which disappointed him.   大多数人没有投票支持他，这使他感到失望。

I have told them the reason, for which I changed my mind.   我已经告诉了他们我改变主意的原因。

②关系代词的替代情况不同

a.关系代词whom在限制性定语从句句中作宾语时可用who/that代替，但在非限制性定语从句中作宾语时不可用who/that代替。

This is the man whom/who/that they are taking about.  这就是他们正在谈论的那个人。(限制性定语从句)

The young man had a new girlfriend, whom he wanted to impress.这个年轻人交了一个新女朋友，他想给她留下深刻印象。(非限制性定语从句)

b.在限制性定语从句中，先行词指人时，关系代词可以用 who, that或whom; 但在非限制性定语从句中，先行词指人时,关系代词只能用who或whom。

She has a younger brother, who is an English teacher. 她有一个弟弟，他是一名英语老师。

③关系代词的省略情况不同

关系代词在限制性定语从句中作宾语时可省略，而非限制性定语从句的所有关系词均不可省略。

The film (which/that) I saw a few days ago is well worth seeing.  我几天前看过的那部电影很值得一看。(限制性定语从句)

The film, which I saw a few days ago, is well worth seeing.  这部电影很值得一看，我几天前看过。(非限制性定语从句)

Lucy has an elder brother who works in a hospital.  露西有一个在医院工作的哥哥。(限制性定语从句) .

Lucy has an elder brother, who works in a hospital. 露西有一个哥哥，他在医院工作。(非限制性定语从句)

Mindmap解析

习题-Exercises

语法填空

1．On the 1,100 kilometer journey, the man Cao Shengkang, ________ lost his eyesight at the age of eight in a car accident, crossed 40 cities and counties in three province.

2．He later set up China’s first draft bank, Rishengchang, ________ later had 35 branches across the country.

3．In China, chopsticks are called kuaizi,________is a word made up of characters meaning quick and “bamboo”.

4．But Sarah, ___________has taken part in shows along with top models, wants to prove that she has brains as well as beauty.

5．There are a wide variety of activities at the festival, most of _________ are popular among young people.

6．We all know that there are various types of pollution around us, ________ may cause different kinds of environmental problems.

7．In their class there are altogether 54 students, half of ________ wear glasses.

8．The result was not the same as they had expected, ________ was rather disappointing.

9．Recently I bought an ancient vase, the price of ________ was very reasonable.

10．He had skin cancer, ________ made him ready to give up.

定语从句 3 – 非限制性定语从句最先出现在Clarissa Study。