一、概说

定语从句即指在主从复合句用作定语的从句。定语从句通常修饰名词或代词，对它进行限制、描绘和说明。受定语从句修饰的词语叫先行词，引导定语从句的词语叫关系词。关系词按其性质又分关系代词和关系副词。关系词不仅引导定语从句，同时还在定语从句充当一定的句子成分。

如：The girl who spoke is my best friend. 讲话的姑娘是我最好的朋友。

此句中，who spoke是由关系代词who引导的定语从句，用以修饰先行词the girl，同时who 在定语从句中用作主语。

This is the town where I was born. 这就是我出生的城市。

此句中，where I was born是由关系副词where引导的定语从句，用以修饰先行词the town，同时where在定语从句中用作状语。

二、关系词的用法与辨析

1. 关系词的用法

关系词分关系代词和关系副词。关系代词主要的有 that, who, whom, whose, which, as 等，其中who和whom 只用于指人，which和as 只用于指事物，whose和 that既可于指人也可用于指物，它们在定语从句可用作主语、宾语、表语或定语;关系副词主要有when, where 和why，其中when表示时间，where表地点，why表原因，它们在定语从句中均用作状语：

A plane is a machine that can fly. 飞机是一种能飞行的机器。(that指物，在从句中用作主语)

I have forgotten everything that I learnt at school. 我把学校学的所有东西都给忘了。(that指物，在从句中句作宾语)

The man who lives in that house is my uncle. 住在那座房子里的人是我叔叔。(who指人，在从句中作主语)

The house whose windows are broken is empty. 破了窗户的那座房子是空的。(whose指物，在从句中作定语)

There are some students whose questions I can’t answer. 有些学生提出的问题我回答不了。(whose指人，在从句中作定语)

He is not such a fool as he looks. 他并不像他看起来那么傻。(as指人，在从句作表语)

2. 关系词的选择

选择关系词可考虑以下四点：

(1) 一看先行词的意义，即分清先行词是指人、指物、时间、地点还是原因(如指物时不能用who或whom，指人时通常不用which等)。

(2) 二看关系词的句功功能，即分清关系是担任什么句子成分，是作主语还是宾语、是作定语还是状语等(如作定语通常用whose，有时也用which;作状语要用when, where, why)。

(3) 三看定语从句的种类，即分清是限制性定语从句还是非限制性定语从句(如that和why通常不引导非限制性定语从句)。

(4) 四看文体，即分清是正式文体还是非正式文体，是书面语体还是口语体。

3. 关系词的辨析

(1) 关于关系代词that与which的区别、that与who的区别、who与whom的区别、as与which的区别等。

(2) 关系副词when, where与why的区别是：when用于指时间，where用于指地点，why用于指原因：

1980 was the year when he was born. 1980是他的出生年。

This is the room where he lived. 这就是他曾住过的房间。

These are the reasons why we do it. 这些就是我们这样做的理由。

三、关系词的省略

关系词有时可以省略，但这只限于限制性定语从句中，在非限制性定语从句中，关系词则不可省略。

1. 关系代词作宾语时的省略

当关系代词who, whom, which和that在定语从句中用作动词宾语或介词位于句末时的介词宾语时，可以省略：

Is there anything (which) you wanted? 想要什么东西吗?

Who is the man (that / who / whom) you were talking to? 刚才和你讲话的人是谁?

2. 关系代词作表语时的省略

当关系代词that在定语从句中用作表语时，可以省略：

China is not the country (that) it was. 中国已不是过去的中国了。(that作表语)

3. 关系代词作宾语补足语时的省略

当关系代词that在定语从句中用作宾语补足时，可以省略：

I’m not the madman (that) you thought me. 我并不是你所认为的那个疯子。(that作宾语补语)

4. 关系代词作主语时的省略

一般说来，关系代词作主语时是不能省略的，但是在以下两种特殊情况，也可省略：

(1) 当定语从句为there be 结构时，作主语的that可以省略：

I’ve told you all (that) there is to tell. 该告诉的我都告诉你了。

(2) 当主句为there be结构时，在定语从句中作主语的that, which, who有时可省略：

There’s a gentleman (who) wants to see you. 有一位先生要见您。

(3) 当主句为it is结构时，在定语从句中作主语的that也可省略：

Here’s a little book (that) will tell you how to raise roses. 这是一本关于玫瑰花栽培的小册子。

5. 关系副词when的省略

用作时间状语的关系副词when通常不能省略，但有一种特殊情况，即用于day, year, time等少数几个词后时可以省略(也可换成that)：

That was the year (that) I first went abroad. 就是那一年我第一次出国了。

I’ll never forget the day (that) we met. 我永远也忘不了我们见面的那一天。

6. 关系副词where的省略

用作地点状语的关系副词where通常不能省略，但有一种特殊情况，即用于place, somewhere, anywhere, everywhere, nowhere少数几个词后时可以省略(也可换成that)：

This is the place (where) they met yesterday. 这就是他们昨天碰头的地方。

Have you somewhere (that) I can lie down for an hour? 你有没有一个什么地方可以让我躺一个小时?

7. 关系副词why的省略

关系副词why通常只用于the reason后引导定语从句，且通常可换成that或for which，均可省略：

That’s the reason (why, for whih, that) he came. 这就是他来的原因。

四、限制性定语从句与非限制性定语从句

1. 形式不同

限定性定语从句主句和从句之间不用逗号隔开，口语中使用时也不停顿;而非限定性定语从句与主句之间通常有逗号隔开，口语中使用时有停顿。

2. 功能不同

限定性定语从句用于对先行词的意义进行修饰、限制和识别，如果去掉，就会造成句意不完整或概念不清;而非限定性定语从句用于对先行词起补充说明作用，如果省略，句意仍然清楚、完整：

People who take physical exercise live longer. 进行体育锻炼的人活得长些。(若把从句去掉句子就失去意义)

His daughter, who is in Boston now, is coming home next week. 他女儿现在在波士顿，下星期回来。(若把从句去句子意义仍然完整)

3. 翻译不同

在翻译定语从句时，一般把限定性定语从句翻译在它所修饰的先行词之前，而把非限定性定语从句与主句分开：

He is the man whose car was stolen. 他就是汽车被窃的那个人。

I’ve invited Jim, who lives in the next flat. 我邀请了吉姆，他就住在隔壁。

4. 含义不同

比较：

I have a sister who is a doctor. 我有一个医生的姐姐。(姐姐不止一个)

I have a sister ,who is a doctor. 我有一个姐姐，她是当医生的。(只有一个姐姐)

5.先行词不同

限定性定语从句的先行词只能是名词或代词，而非限定性定语从句的先行词则可以是名词或代词，也可以是短语或句子;另外，当先行词为专有名词或其他具有独一无二性的普通名词时，通常要用非限制性定语从句，而不用限制性定语从句：

Peter drove too fast, which was dangerous. 彼得开车很快，这是很危险的。(which指drive too fast)

He changed his mind, which made me very angry. 他改变了主意，这使我很生气。(which指整个主句)

Mr. Smith, who is our boss, will leave for Japan next week. 我们的老板史密斯先生下周要去日本。(先行词为专有名词，要用非限制性定语从句修饰)

Her father, who has a lot of money, wishes her to study abroad. 她父亲很有钱，希望她出国学习。(先行词为表独一无二意义的普通名词，要用非限制性定语从句修饰)

6. 关系词不同

关系词that和why可用于限制性定语从句中，通常不用于非限制性定语从句;另外，在限制性定语从句中，关系词有时可以省略，而在非限制性定语从句中关系词一律不省略。

五、紧缩的定语从句

1. 关于“介词+关系代词+不定式”

该结构主要用于正式文体中，相当于一个被紧缩的定语从句：

She must have time in which to grow calm. 她必须有冷静下来时的时间。

Allow me one minute in which to change my clothes. 给我一点时间换衣服。

He was miseralbe unless he had neighbours with whom to quarrel. 他要是没有邻居吵架就难受。

注意，该结构中的介词不能没有，也不能位于不定式后面：

在那儿孩子们有个玩耍的花园。

正：There the children had a garden in which to play. (很正式)

正：There the children had a garden in which they could play. (较正式)

正：There the children had a garden to play in. (较口语化)

误：There the children had a garden which to play in.

2. 将定语从句转化为分词短语

有时为了简洁起见可将定语从句转化为分词短语作定语：

Who’s the girl who is sitting beisde Jim? / Who’s the girl sitting beside Jim? 坐在吉姆旁边的女孩是谁?

Most of the people who were invited to the party were teachers. / Most of the people invited to the party were teachers. 应邀参加晚会大多数是教师。

Anyone who touches that wire will get a shock. / Anyone touching that wire will get a shock.任何人触到那根电线都会遭到电击。

注意，并非所有的定语从句都能转换成分词短语，比如那些不能后置定语的分词短语就不能与定语从句进行转换：

误：This is the boy being from the country. (being引出的分词短语通常不用定语，除非它是构成被动语态的助动词)

正：This is the boy who is from the country. 这是来自乡下的那个男孩。

误：We caught the thief having stolen the car. (现在分词完成式不用作定语，即使换成一般式也不对，因为现在分词短语作定语时它不能先于谓语动作之前发生)

正：We caught the thief having stolen the car. 我们抓住了偷汽车的小偷。

六、应考定语从句的几个易错点：

1. 混淆定语从句与并列句

请看下面两题：

(1) He has two children, and both of _____ are abroad.

A. them B. which C. whom D. who

(2) He has two children, both of _____ are abroad.

A. them B. which C. whom D. who

第(1)题选A，第(2)题选C。由于第(1)题中用了并列连词and，从而使整个句子为并列句，and后应是一个独立的简单句，所以选A不选C;第(2)题没有并列连词and，both of whom are abroad为非限制性定语从句。

2. 混淆定语从句与表语(从句)

请看下面的试题：

(1) Your coat is still _____ you left it.

A. where B. there C. there where D. the place where

答案选A，where引导的是表语从句(=在…的地方)，而不是定语从句。

(2) Is this school _____ your father worked in ten years ago?

A. where B. what C. that D. the one

答案选D，this school为句子主语，the one 为表语，your father worked in…为定语从句。不要误认为this是句子主语，否则school前应加冠词the。

比较：

Is this the school _____ your father worked in ten years ago?

A. where B. what C. that D. the one (选C)

Is this the school _____ your father worked ten years ago?

A. where B. what C. that D. the one (选A)

3. 混淆定语从句与状语从句

请看下面的试题：

(1) I went upstairs ______I heard some crying.

A. where B. when C. that D. which

答案是B而不是A，when的意思是“当…的时候”，引导的是时间状语从句。(upstairs为副词，不宜用作先行词)

(2) He is _____ a clever boy _____ we all like.

A. such, that B. such, as C. so, that D. so, as

答案应选B，而不是A。such … that …(如此…以致…)用于引导结果状语从句，其中的that不充当句子成分，而such…as…中的as为关系代词，用以引导定语从句并在定语从句充当句子成分。上句中第二空之所以选as，是因为它用作动词like宾语。

4. 误加与关系代词同义的人称代词

误：He is a man everyone respects him.

正：He is a man everyone respects. 他是一个人人都敬重的人。

5. 混淆关系代词与关系副词

有的同学一看到先行词是表示时间、地点、原因的名词，就认为一定要用关系副词，其实也一定。在此情况下，还要看关系词在定语从句中是用作什么成分，若是用作状语，则用关系副词，若不是用作状语(如用作主语、宾语等)则不能用关系副词，而用关系代词。

比较：

This is the factory where I want to work. 这就是我想工作的工厂。(work为不及物动词where在从句中用作状语)

This is the factory that I want to visit. 这就是我想参观的工厂。(visit为及物动词，that用作visit的宾语)

The reason why he can’t come is that he is ill. 他没来的是因为他病了。(come为不及物动词，why在定语从句中用作状语)

The reason that he put forth is very important. 他提出的理由很重要。(put forth为及物动词，that在定语从句中用作其宾语)

6. 因逗号误判which

有的同学一看见逗号，就以为一定要选which而不选that，但问题是有时根本就不是定语从句：

(1) If a book is in English, _____ means slow progress for you.

A. as B. which C. what D. that

(2) When I say two hours, _____ includes time for eating.

A. as B. which C. what D. that

以上两题均应选that，而不能选which，因为它们根本不是定语从句。之所以选that，是因为句中已有if和when引导的状语从句，逗号后为主句，that为主句主语。

7. 混淆which与whose

两者在定语从句中都可用作定语，区别是：whose 的意思相当于 one’s，而 which 的意思则相当于 that 或 this。

比较：

(1) This is Mary, whose [= and her] father we met last week.

(2) Call again at 11, by which time [= and by that time] the meeting should be over.

七、重点考点原创精练

1. He wrote a lot of novels, many of _____ translated into foreign languages.

A. it B. them C. which D. that

2. He wrote a lot of novels, many of _____ were translated into foreign languages.

A. it B. them C. which D. that

3. He wrote a lot of novels, and many of _____ were translated into foreign languages.

A. it B. them C. which D. that

4. Mr Smith is _____ a good teacher _____ we all respect.

A. such, that B. such, as C. so, that D. so, as

5. She may have missed the train, in _______ case she won’t arrive for another hour.

A. whose B. that C. which D. what

6. If he’s only interested in your looks, _____ just shows how shallow he is.

A. as B. which C. what D. that

7. It was in the small house _____ was built with stones by his father _____ he spent his childhood.

A. which, that B. that, which

C. which, which D. that, where

8. I believe the time will soon come ______ there will be no weapons in the world.

A. since B. that C. where D. when

9. The meeting was put off, _____, of course, was exactly what we wanted.

A. who B. which C. this D. what

10. The train, _____ takes only two hours to get there, is quicker than the bus, _____ takes three.

A. which, it B. it, which

C. which, which D. it, it

11. Mr Smith has bought a little house in the country, around _____ some green trees.

A. which is B. it is C. which are D. them are

12. He is always really rude, ______ is why people tend to avoid him.

A. that B. it C. this D. which

13. The crisis has reached a point ______ the receiver will have to be called in.

A. when B. where C. that D. who

14. In 1980 he caught a serious illness from _____ efforts he still suffers.

A. which B. that C. whose D. what

15. I’m looking for a new job, one _____ I get a bit more job satisfaction.

A. when B. where C. that D. which

16. They found a strange book, parts of _____ were difficult to understand.

A. that B. which C. what D. this

17. What have you got _____ will help a cold?

A. what B. that C. it D. who

18. Is there a shop around ______ we can buy some toilet articles?

A. that B. which C. where D. what

19. Unless I’m very much mistaken, ______ is my watch you’re wearing!

A. as B. which C. what D. that

答案：

1—5 BCBBC 6—10 DADBC 11—15 CDBCB 16—19 BBCD