在复合句中作定语，修饰主句中的某一名词或代词的从句，叫做定语从句。
被定语从句所修饰的词叫先行词，位于从句之前。定语从句有关系代词that、which、who、whose、whom和关系副词when 、where、why引导.
定语从句的基本结构为：
先行词 + 关系代/副词 + 句子
考点1. 关系代词: that, which, who, whom, whose 关系副词: when, where, why.
a. that-既可指人，也可指物，作主语，不能省略;作宾语，可以省略;不引导非限定性定语从句
There are lots of things ________ I need to prepare before the trip. (10河北)
A. who B. that C. whom D. whose
(答案: B)
b. which-指物，作主语，不能省略;作宾语，可以省略.可引导非限定性定语从句。
This is the dictionary ________ Mum gave me for my birthday. (08河北)
A. which B. what C. whose D. whom
(答案：A)
Sorry, we don’t have the coat ________ you need. (09河北)
A. what B. who C. whom D. which
(答案：D)
c. who-般指人，作主语，不能省略;作宾语，可以省略,(常用whom)
Jamie is a young cook ________ wants to improve school dinners. (10天津)
A. who B. whose C. whom D. which
(答案：A)
d. whose 作定语,表示所属关系。
I like the teacher ________ classes are very interesting and creative. (09兰州)
A. which B. who C. what D. whose
(答案：D)
e. when 作时间状语:When =介词 + which
She will never forget the day when (=on which) she was married.
f. where 作地点状语 where = 介词 + which
I want to know the place where (= in which) I was born.
g. why 作原因状语, 其先行词常常是the reason. why = for which
That is the reason why(= for which) I’m late.
2. 当关系代词在定语从句中作主语时,定语从句的谓语动词形式由先行词定。
3. 有时只能用 that , 不用 which, 常见的情况有六种：
1).当先行词是 all, any, few, little, none, anything, everything, nothing ,或被它们修饰时。
That’s all that I know.
Is there anything that I can do for you?
2).当先行词被形容词最高级或序数词修饰That is the most interesting book that I have ever read.
3).当先行词有the very, the only, the same等修饰时。
That’s the only thing that I can do now. These are the very words that he used.
4).当主句以 who 或 which开头时，定语从句的关系词用 that, 而不用 which 或 who.
Who is the girl that spoke to you just now? Which is the pen that you lost ?
5).先行词同时包括人或物时，关系词用that.
The man and his dog that I always meet are standing by the gate.
6).当关系代词在从句中作表语时。
China is not the country that it was.
4. 只用 which ,不用that 的情况：
1).关系代词前有介词时。
This is the cage that / which Polly lives in.
= This is the cage in which(where) Polly lives .
2).先行词本身为 that.
The clock is that which tells the time.
3). 在非限制性定语从句中。
His English, which used to be poor , is excellent now.
定语从句专项练习
1.Sorry, we don’t have the coat ________ you need.
A. what B. who C. whom D. which
2.This is the dictionary ________ Mum gave me for my birthday.
A. which B. what C. whose D. whom
3.Do you know the man ________ is sitting behind Nancy?
A. what B. which C. who D. whom
4.The book ________ he bought yesterday is very interesting.
A. / B. why C. when D. what
5.I have found some pictures of the most interesting places ________ you can visit during the winter holidays.
A. where B. which C. what D. that
6.I’d like to tell you about the table manners ________ you should know when you visit Korea.
A. which B. who C. what D. how
7.I shall never forget those years ________ I lived on the farm with the farmers, ________has a great effect on my life.
A. when; who B. that; which
C. which; that D. when; which
8.Is oxygen the only gas ________ helps fire burn?
A. that B. / C. which D. it
9.Is ________ some German friends visited last week?
A. this school B. this the school
C. this school one D. this school where
10.---What kind of music do you like?
---I like music ________ has great lyrics.
A. that B. what C. who D. whose
11.That is the only thing ________ I bought from the supermarket.
A. which B. that C. what D. where
12.The place ________ interested me most was the Children’s Palace.
A. which B. where C. what D. in which
13.The computer ________ last week has gone wrong.
A. which I bought it B. I bought
C. what I bought D. I bought it
14.That is the poor boy ________ father died in a traffic accident last year.
A. who B. whom C. whose D. which
15.Do you know the girl ________ is standing under the tree?
A. who B. whom C. which D. where
16.Is the woman ________ talked to our teacher yesterday your mother?
A. who B. whom C. which D. what
17.The young lady ________ we met yesterday is our new maths teacher.
A. what B. whose C. whom D. which
18.I like to live in a house ________ is big and bright.
A. that B. who C. how D. why
19.I hate people ________ talk much but do little.
A. whom B. which C. who D. when
20.I am one of the boys ________never late for school.
A. that is B. who are C. who am D. who is
21.Mr Green, there is someone at the front desk ________ would like to speak with you.
A. he B. who C. which D. whom
22.I love the small village ________ I was born.
A. that B. which C. where D. whose
23.Here comes the girl ________ handwriting is the best in our class.
A. which B. whose C. that D. who
24.My parents usually buy me some simple clothes ________ can last a long time.
A. who B. that C. whom D. whose
25.---Is the girl ________ is interviewing the manager of that company your friend?
---Yes, she is a journalist from CCTV.
A. whom B. which C. who D. whose
26.---Do you know everybody ________ came to the party?
---No, I don’t know the one________ you had a long talk with near the door.
A. who;/ B. whose; that
C. that; which D. /; whom
27.The boy________ won the first prize is called Roy.
A. when B. whom C. who D. which
28.Children like houses ________ are painted in different colours.
A. which B. they C. those D. what
29.Do you think most students prefer tests ________ have easy questions?
A. who B. where C. that D. it
30. He is one of the experienced engineers in this factory ________ hard work was repaid with the development of the factory.
A. where B. whose C. in which D. that
Keys:
1-5 DACAD
6-10 ADABA
11-15BABCA
16-20 ACACB
21-25 BCBBC
26-30ACACA