在复合句中修饰名词和代词的从句叫做定语从句.
被定语从句修饰的名词或代词叫做先行词.
引导定语从句的关系代词有who, whose, whom, which, that, as ;
引导定语从句的关系副词有when, where, why;
关系代词在定语从句中做主语,宾语,定语.
关系副词在定语从句中做状语.
一.由 who, 引导的定语从句,who在从句中做主语(口语中也可做宾语),
修饰表示人的先行词. 例如:
This is the man who helped me.
Do you know the comrade who spoke just now ?
The boy who//whom we saw yesterday is John’s brother.
二.whom引导的定语从句,whom在从句中作宾语,修饰表示人的先行词,
口语中可以省略.
The doctor (whom) you are looking for is in the room.
The person (whom) you just talked to is Mr. Li.
=The person to whom you just talked is Mr. Li. (介词后 whom不能省略)
The babies whom the nurses are looking for are very healthy.
(固定短语中的介词一般不省略,介词仍放在动词之后)
三.whose引导的定语从句,whose在从句中作定语,修饰表示人或物的先行词.
Do you know the woman whose name is Mary.
Pass me the dictionary whose cover is black.
四.that引导的定语从句,that在从句中做主语或宾语,修饰表示人或物的先行词,
作宾语时可省略,不能放在介词后面作宾语.
The letter (that//which) I received was from my father.
I can’t find the letter that//which came this morning.
Do you still remember the days (that//which)we spent together ?
This is the man that//who helped me.
The house (that//which) we live in is not large.
=The house in which we live is not large.
The doctor (that//whom //who)you are looking for is in the room.
五. which引导的定语从句,which在从句中做主语,也可做宾语,或介词的宾语,
修饰表示物的先行词. 先行词可以是词、短语、句子.
This is the book (which/that ) you want.
The building which//that stands near the river is our school.
The room in which there is a machine is a workshop.(介词后面的which不能省略)
The house (which/that) we live in is not large.
This is the watch (which/that ) he was looking for.
(在含有介词的动词固定词组中,介词只能放在动词之后,不能放在which之前 )
六、that 和which 都可以修饰表示物的先行词, 但是下列情况只能用that.
①. 先行词为不定冠词all, few, little, much, everything, nothing 等.
All (that) you have to do is to practise every day.
There isn’t much (that) I can do.
②. 先行词被序数词或形容词的最高级所修饰时.
The first lesson (that) I learned will never be forgotten.
This is the best film (that ) I have ever seen.
③. 先行词被all, any, every, few, little, no, some 等不定代词修饰时.
I have read all the books (that) you gave me.
④. 先行词被the only, the very, the last, the same 等修饰时.
The white flower is the only one that I really like.
This is the very book that I want to read.
This is the same book that I want to read. (同一本书)
----This is the same book as I want to read.
⑤. 当主句以who或 which 开头的特殊疑问句时,定语从句that 引导.
Who is the man that is standing there ?
Which of us that knows something about physics doesn’t know this ?
⑥先行词既有人又有物时.
We talked about the persons and things that we could remember.
⑦time做先行词,前面如果有序数词或 last 来修饰时,定语从句用 that 来引导或省略；如果没有序数词或 last 来修饰时,既可用 when 也可用that来引导.
This is the last time ( that ) I shall give you a lesson.
The first time ( that ) I saw him was in 1972.
It’s time ( that ) we got up.
七、as 引导的定语从句,
as用作关系代词和关系副词引导限定性定语从句,在从句中作主语、定语、表语、或状语,常与the same … as; such… as , so… as , as… as 连用.
I like the same book as you do.
I want to have such a dictionary as he has.
I shall do it in the same way as you did.
He is the same age as you ( are ).
He will give you such information as will help you.
Such students as you have mentioned should be criticized.
=Students such as you have mentioned should be criticized.
在the same…后也可用that引导定语从句,但意义有所不同：
that 引出的定语从句,指的是与先行词同一事物；而 as引出的定语从句是与先行词相似的'同类事物.
I want to use the same tool that I used yesterday.
I want to use the same tool as I used yesterday.
八、由when 引导的定语从句,修饰表示时间的先行词,when为关系副词,
做定语从句的时间状语.
I still remember the day when I first came to Beijing.
I still remember the day on which I first came to Beijing.
( 介词＋which可以代替 when)
I’ll never forget the time when we worked on the farm.
[I remember the days which//that we spent together.]
九、由where 引导的定语从句,修饰表示地点的先行词,where为关系副词,
做定语从句的地点状语.
This is the place where we lived for five years.
The factory where his father works is in the west of the city.
The factory in which his father works is in the west of the city.
( 介词＋which可以代替where)
[ This is a place which//that I wanted to visit. ]
十、Why引导的定语从句,why做原因状语.
I know the reason why he came late.
The reason why he was late was that he was ill.
非限定性定语从句
1. who 指人,做主语.
Yesterday I met Li Ping, who seemed to be very busy.
2. whom 指人, 作宾语.
He had many friends, many of whom had been in the universities.
3. whose 指人, 作定语.
The Chairman’s daughter, whose name is Ann, gave Tom a smile.
4. which 指物, 做主语,宾语.
His speech, which bored everyone, went on and on.
The speech, which he had written on the paper, seemed endless.
5. where 指地点, 作状语.
Galileo lived in the city of Pisa, where there is a leaning tower about 180 feet high.
6. when 指时间,作状语.
The meeting will be put off till next month, when we will have made all the preparations.
7. as 做主语,表语,宾语; 先行词可以是一个词,一个短语或一个句子.
To shut your eyes to facts, as many of you do, is foolish.
As we all know, he studies very hard.
As 引导的定语从句可放在主句前,也可放在主句后.在很多情况下已经
构成固定搭配.
As everybody can see as was usual
As can be seen as I expected
As is known to all, as may be imagined
as you know as is expected
as has been said before as is reported
as is often said as is announced
限定性定语从句和非限定性定语从句的区别：
限定性定语从句是先行词在意义上不可缺少的定语,如果去掉,主句的意思就不完整或失去意义.这种从句和主句的关系十分密切,写时不用逗号分开.
非限定性定语从句和主句的关系不十分密切,只是对先行词作些附加的说明,如果去掉,主句的意思依然清楚.这种从句和主句之间往往用逗号分开,一般不用that 引导.
as和 which 引导的非限定性定语从句的比较：
1. 非限定性定语从句位于句未,而且as 和which 在从句中作主语、宾语、表语时可互换.
He is a farmer, as/which is clear from his manner.
This elephant is like a snake, as/which anybody can see.
2.which 引导的非限定性定语从句一般放在句未,而as 引导的非限定性定语从句可放在句未,也可放在句中、句首. 放在句首时不能用which 替换.
Crusoe lost his dog, which made him very sad
Taiwan is part of China, as/which is known to all.
As we have seen, oceans cover more than 70 percent of the earth.
3.as引导非限定性定语从句时,意为“这一点、这件事”,常与 see, hope,expect,know,guess等动词搭配；而which引导非限定性定语从句时与主句有一种因果关系,可译为“所以……”.
Cyprus, as you all know, is in the Mediterranean.
Bamboo is hollow, which makes it very light.
4. as引导非限定性定语从句并在从句中作主语时,其后面的谓语动词大多数必须是连系动词.如果从句谓语动词是行为动词,则必须用which.
He married her, as was natural.
She refused to take the medicine, which made her mother angry.
一、定义
定语从句是指在句中做定语作用，修饰句中的名词或代词的从句，其中被修饰的名词或代词为先行词。当关系代词作定语从句的主语时，其后的谓语动词的人称和数取决于先行词的人称和数。
二、定语从句的结构
定语从句一般位于先行词的后面，定语从句由关系代词who, whom, whose, that, which，that, as和关系副词when, where, why等引导。
(一)关系代词引导的定语从句
关系代词所代替的先行词是人或物的名词或代词，并在句中充当主语、宾语、定语等成分。关系代词在定语从句中做主语时，从句谓语动词的人称和数要和先行词保持一致。
(1)who, whom, that
这些词代替的先行词是人的名词或代词，在从句中做主语和宾语。例如：
·Is he the man who/that wants to see you?
他就是你想见的人吗?(who/that在从句中做主语)
·He is the man whom/ that I saw yesterday.
他就是我昨天见的那个人。(whom/that在从句中做宾语)
(2)whose 用作关系词表示所属格，也可看作是关系形容词，因为它后面必须接一个名词连用。不能单独使用。例如：
·They rushed over to help the man whose car had broken down.
那人车坏了，大家都跑过去帮忙。
(3)which, that所代替的先行词是事物的名词或代词，在从句中可做主语、宾语等。作宾语时常可省略。例如：
·A prosperity which / that had never been seen before appears in the countryside.
农村出现了前所未有的繁荣。(which / that在句中作宾语)
(二)关系副词引导的定语从句
关系副词可代替的先行词是时间、地点或理由的名词，在从句中作状语。
(1)关系副词when, where, why的含义相当于“介词+ which”结构，因此常常和“介词+ which”结构交替使用。例如：
·There are occasions when(on which)one must yield.
任何人都有不得不屈服的时候。
·Beijing is the place where(in which)I was born.
北京是我的出生地。
·Is this the reason why(for which)he refused our offer?
这就是他拒绝我们帮助他的理由吗?
(2)that代替关系副词，可以用于表示时间、地点、方式、理由的名词后取代when, where, why和“介词+ which”引导的定语从句，在口语中that常被省略。例如：
·His father died the year(that / when / in which)he was born.
他父亲在他出生那年逝世了。
·He is unlikely to find the place(that / where / in which)he lived forty years ago.
他不大可能找到他四十年前居住过的地方。
(三)限制性和非限制性定语从句
(1)定语从句有限制性和非限制性两种。
限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确;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。例如：
·This is the house which we bought last month.
这是我们上个月买的那幢房子。(限制性)
·The house, which we bought last month, is very nice.
这幢房子很漂亮，是我们上个月买的。(非限制性)
(2) 当先行词是专有名词或物主代词和指示代词所修饰时，其后的定语从句通常是非限制性的。例如：
·Charles Smith, who was my former teacher, retired last year.
查理·史密斯去年退休了，他曾经是我的老师。
·My house, which I bought last year, has got a lovely garden.
我去年买的那幢房子带着个漂亮的花园。
·This novel, which I have read three times, is very touching.
这本小说很动人，我已经读了三遍。
(3) 非限制性定语从句还能将整个主句作为先行词, 对其进行修饰, 这时从句谓语动词要用第三人称单数。例如：
·He seems not to have grasped what I meant, which greatly upsets me.
他似乎没抓住我的意思，这使我心烦。
·Liquid water changes to vapor, which is called evaporation.
液态水变为蒸汽，这就叫做蒸发。
说明：关系代词that和关系副词why不能引导非限制性定语从句。
(四)介词+关系词
(1)介词后面的关系词不能省略。
(2)that前不能有介词。
(3)某些在从句中充当时间，地点或原因状语的“介词+关系词”结构可以同关系副词when 和where 互换。例如：
·This is the house in which I lived two years ago.
这是我两年前住过的房子。
·This is the house where I lived two years ago.
·Do you remember the day on which you joined our club?
还记得你加入我们俱乐部的那一天吗?
·Do you remember the day when you joined our club?
(五)as, which 引导的非限定性定语从句
由as, which 引导的非限定性定语从句，as和which可代整个主句，相当于and this或and that。As一般放在句首，which在句中。例如：
·As we know, smoking is harmful to one's health.
如我们所知，吸烟有害健康。
·The sun heats the earth, which is very important to us.
太阳使地球暖起来，这对我们人类很重要。
【特别提示】 as 和which在引导非限制性定语从句时，这两个关系代词都指主句所表达的整个意思，且在定语从句中都可以做主语和宾语。但不同之处主要有两点：
a)as 引导的定语从句可置于句首，而which不可。
b)as 代表前面的整个主句并在从句中做主语时，从句中的谓语必须是系动词;若为行为动词，则从句中的关系代词只能用which.。
首先,所有的句子都是完整的句子!
第一句：that 作定语从句的主语,句子是主谓结构.如果加it,就与that重复了(两个主语了).
你不要忘了：定语从句的引导词是要在句中作成分的.这点与that 引导宾语从句不做成分截然不同.一般that在定语从句中作主语或宾语.如 The boy that likes English is Tom.(that作主语,千万别再加he),
The bike that you bought is very nice.(作宾语)
第二句：that 作定语从句的宾语.tell 可带双宾语,即tell sb sth,本句中,you (sb) 和 much (sth) 都是宾语.
定语从句:在复合句中修饰名词或代词的句子在复合句中充当定语,所以叫作定语从句.
先行词：定语从句所修饰的名词或代词.
关系词：引导定语从句的词,分为关系代词（who,whom,that,which,whose）和关系副词(where,when,why,).
复合句 ：The man who (that) came is Mike.
先行词 关系代词
Li Ming is the one that got full marks in our class.
先行词 关系代词
上句的黑体字为复合句中的主句,蓝体字为定语从句.
一 定语从句的.关系代词 Which的用法:若先行词指物则代替先行词在定语从句中充当主语或宾语.
This is the pen which was given by my friend.
先行词 指物代替先行词在定语从句中充当主语
This is the pen which my friend gave to me.
先行词 指物代替先行词在定语从句中充当宾语
二 定语从句的关系代词 Who的用法:若先行词指人则代替先行词在定语从句中充当主语或宾语(如果前面带介词则必须用whom)
The man who is wearing a white suit is my brother.
先行词 指人代替先行词在定语从句中充当主语
The man whowhom he wanted to see last week is in Shanghai.
先行词 指人代替先行词在定语从句中充当宾语
She is the girl with whom I went there.
先行词 指人代替先行词在定语从句中充当介宾且介词于前.
三 定语从句的关系代词 Whom的用法:若先行词指人则代替先行词在定语从句中充当宾语(包括介词的宾语) ,与who的区别是如果前面带介词则必须用whom
This is the teacher whomwho we like best.
先行词 指人代替先行词在定语从句中充当宾语
She is the girl whom who I went with there.
先行词 指人代替先行词在定语从句中充当介宾.
I don’t like the boy to whom you are talking.
先行词 指人代替先行词在定语从句中充当介宾且介词于前.
四 定语从句的关系代词 that的用法:若先行词指人或物则代替先行词在定语从句中充当主语或宾语
The animal that which is lost is a panda.
先行词 指物代替先行词在定语从句中充当主语
She is the person that who we are worried about.
先行词 指人代替先行词在定语从句中充当宾语
注意1 that which在代物时常常可以通用,但有时只宜于用which ,不用that
(1) 关系代词前有介词时.
This is the hotel in which you will stay.
(2) 如有两个定语从句,其中一句的关系代词是that,另一句宜于用which.
Let me show you the novel that I borrowed from the liberary which was newly open (新开放) to us.
注意2that which在代物时常常可以通用,但有时只宜于用that ,不用which.
(1) 先行词是形容词最高级或者它的前面有形容词最高级时
This is the best that has been used against air pollution(反对空气污染) in cities.
English is the most difficult subject that you will learn during these years.
(2) 先行词是序数词,或它的前面有一个序数词时
He is the last person that I want to see.
(3) 主句中已有疑问词时
Which is the bike that you lost?
(4) 先行词既有人又有物时
The bike and its rider that had run over (撞倒了)an old man were taken to the police station.
(5) 先行词是all,much,little,something,everything,anything,nothing,none,the one等代词时
You should hand in all that you have.
We haven’t got much that we can offer you.
I mean the one that you talked about just now.
(6) 先行词前面有only,any,few,little,no,all,one of,the same,the very等词修饰时
The only thing that we can do is to give you some money.
Li Ming is the only one that got full marks (满分)in our class.
Li Ming is one of the students that want to be teachers in our class.
(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
Edison built up a factory(办了一个工厂) which produced things that had never been seen before.
定语从句的关系副词 Where的用法:若先行词指地点且其在定语从句中充当地点状语.
This is the house+I was born in the house.(=I was born there)
介词短语 副词
=This is the house where I was born.这就是我在那儿出生的房子.
先行词 关系副词
in which I was born.
介词+关系代词
which I was born in.
关系代词
这里作介宾的which和that可以省略
that I was born in
