定语从句是高中英语的重点，也是高考英语的重点，不仅在语法填空中会有设题，在阅读和写作中它也有着重要的作用。在讲定语从句前先让同学明白什么是定语。定语时用于修饰名词或代词的词、词组或句子。
- 形容词作定语，放在所修饰词的前面。
red pen 红色的笔，red 就称为pen 的定语，说明名词pen 的状态特征。
2.短语作定语，放在所修饰词的后面
the pen on the table 桌子上的笔。短语on the table是the pen的定语。
The pen on the table is red. 桌子上的笔是红色的。（这个句子的句子成分：The pen 是主语，is 是系动词，red是表语，on the table是the pen的定语。也可以把整个The pen on the table作为主语）
3.句子作定语
the pen I bought yesterday 我昨天买的笔。句子 I bought yesterday是the pen的定语。
The pen I bought yesterday is red. 我昨天买的笔是红色的。（The pen is red 是主系表， I bought yesterday是the pen的定语。）
两个简单句：1. I bought a pen yesterday. 2. The pen is red.
这两个句子的共同部分是pen，现在我们把他们合并成一个带有定语从句的复合句。
以句子2为主句：
The pen that(which) I bought yesterday is red. （用that或which代替句子1中的 a pen 且放在句子1的前面，一并放在主语The pen 的后面，构成修饰The pen 的定语从句。然后把主句中的is red落下来。）
以句子1为主句：
I bought a pen yesterday that(which) is red. （用that或which代替句子2中的 The pen 且放在句子1的后面，修饰 a pen 定作语从句。）
我们把定语从句所修饰的词（即两个简单句中共同的部分，如 The pen）称为先行词
用来代替句子中的共同部分的词，如that或which，称为关系词。
关系词的作用和种类一. 作用
1.引导作用: 引导定语从句
2.指代作用：代替先行词
3.在从句中充当句子成分。这个是考试时我们选择关系词的关键
The pen that(which) I bought yesterday is red. that(which) 代替The pen 在从句中做宾语。还原为 I bought the pen yesterday.
I bought a pen yesterday that(which) is red. that(which) 代替pen 在从句中做主语。还原为The pen is red.
二.种类：根据关系词在从句中所作的成分，分为2种
1.关系代词：who, whom, whose, which, that（当who, which, that作主语时，谓语的单复数应与先行词保持一致。）
The student that answered the question was John.（主语）
The book (that) you lent me was interesting.（宾语，作宾语时可省略）
Football is a game which is liked by most boys. （主语）
This is the pen (which) he bought yesterday. （宾语）
A doctor is a person who looks after people's health.（主语）
The man(who)you met just now is my friend.（宾语）
The man(whom)you met just now is my friend. （宾语）
Mr. Ling is just the boy(whom)I want to see. （宾语）
He has a friend whose father is a doctor.（先行词是人）
Please pass me the book whose (of which) cover is Green.（先行词是物）
2.关系副词：when, where, why，在从句中做状语
I'll never forget the days when I worked together with you
The time when we got together finally came.
This is the mountain village where I stayed last year.
The house where I lived ten years ago has been pulled down
Please tell me the reason why you missed the plane.
I don’t know the reason why he looks unhappy today.
Note:
1.when通常翻译为“在那时”，where通常翻译为“在那儿”，why通常翻译为“...的原因”,注意和引导的状语从句时的翻译是不同的。
2. 关系副词=介词 关系代词
why=for which（先行词一般是reason）
Where=in/ at/ on/ ... which (介词同先行词搭配)
When=during/ on/ in/ ... which (介词同先行词搭配)
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 ,where和why 互换。where = in/at which
when=in/on/at/during which why = for which
whose=of which/whom the 物/人=the 物/人 of which/whom
一.关系代词定语从句的整合与拆分
把下列两个简单句合成带有定语从句的复合句。
1. The boys are from Class One. The boys are playing football.
(1)第一句为主句，第二句为从句，将两个单句合并为一句。
The boys(the boys are playing football) are from Class One.
(2) 括号中句子里的主语the boys, 和先行词是同一个词，应该用关系词替换从句中重复的the boys. The boys 在从句中作主语，关系词中能作主语并代表人的是who, that
The boys(who\that are playing football) are from Class One.
(3) who\that==the boys, 在定语从句中做主语的成分，并连接先行词和定语从句。
2. I found the letter. The letter came yesterday.
(1)第一句为主句，第二句为从句，将两个单句合并为一句。
I found The letter( the letter came yesterday).
(2)用关系词替换从句中重复的the letter, 关系词中能作主语并代表物的是which, that
I found The letter(which\that came yesterday).
(3)which\that==the letter, 在定语从句中做主语的成分，并连接先行词和定语从句。
3. The man is my friend. You met the man just now
(1)第一句为主句，第二句为从句，将两个单句合并为一句。The man (you met the man just now) is my friend.
(2)用关系词替换从句中重复的the man, 关系词中能作宾语并代表人的是whom, that
The man (whom\that you met just now) is my friend.
(3)whom\that==the man, 在定语从句中做宾语的成分，并连接先行词和定语从句。
做宾语的关系词whom\that 可以省略The man ( you met just now) is my friend.
4. I helped the man. The man’s car was broken.
(1)第一句为主句，第二句为从句，将两个单句合并为一句。
I helped the man (the man’s car was broken).
(2) the man’s 是名词所有格，起到定语的作用修饰 car, 用关系词替换从句中重复的the man, 关系词中能作定语，表示“谁的”是whose
I helped the man (whose car was broken).
(3) whose=the man’s, 在定语从句中做定语，并连接先行词和定语从句。
Whose不但可以表示“谁的”，还可以指物，表示“什么的”。例如：
I once lived in a house. The roof of the house has fallen in./ The house’s roof has fallen in.
I once lived in a house (the roof of the house has fallen in)/I once lived in a house (the house’s roof has fallen in.)
此句可改为：
I once lived in a house (the roof of which has fallen in)/(whose roof has fallen in).
介词 关系代词可提前，此句还可改为I once lived in a house (of which the roof has fallen in)
练习
1.The boy came to see me yesterday. He is Tom's brother.
______________________________________________________________________
2. The machines were connected with wires. The wires were very old .
_______________________________________________________________________
3. I know the boy. You gave a book to him.
______________________________________________________________________
4. We had dinner with John. He told us stories about his travels .
____________________________________________________________________
5. Will you please lend me the very book? You bought it last Sunday.
______________________________________________________________________
6. The student is our monitor. Our headmaster praised him at the school meeting.
_____________________________________________________________________
7. He works in a middle school. There is a river in front of the school .
_______________________________________________________________________
8. He used to live in a big house. In front of it grew many banana trees.
________________________________________________________________________
9. They passed a factory. At the back of the factory there were rice fields.
_____________________________________________________________________
10. The soldier ran to the building. On the top of it flew a flag.
_____________________________________________________________________
11. In the evening they arrived at a hill. At the foot of the hill there was a temple.
________________________________________________________________________
12. She came into a big room. In the middle of it stood a large table.
________________________________________________________________________
13.We had to circle around the city in our plane. It looked very beautiful.
________________________________________________________________________
14. Do you know the doctor? He comes here once a month and examines the workers.
________________________________________________________________________
15. The foreign guest is Mr. Green.You saw him at the school gate.
________________________________________________________________________
16. He is the new head. I was talking about him this morning.
_______________________________________________________________________
17. I 've received the book. Father sent it to me
________________________________________________________________________
18.The doctor cured me of fever. He always worked heart and soul .
________________________________________________________________________
19.The experiment failed. The scientist was working on it day and night.
_______________________________________________________________________
20. What's the name of the girl? Her grandpa took part in the Long March.
______________________________________________________________
把下列含有定语从句的句子拆分成两个简单句。
1.The man who has a positive attitude will succeed.
→The man has a positive attitude. He will succeed.
2.The girl who is sitting in the corner is a singer.
→The girl is a singer. The girl is sitting in the corner.
3.The boys(the boys are playing football) are from Class One.
→The boys are from Class One. The boys are playing football.
4.The man who I saw is called Smith.
_______________________________________________________________
5. Her parents wouldn’t allow her to marry anyone whose family was poor.
_______________________________________________________________
6.The person (whom) you wish to see has come.
_______________________________________________________________
7.I feel sorry for famous people who live their lives in the glare of publicity.
_______________________________________________________________
8. A child whose parents are dead is called an orphan
_______________________________________________________________
9.He's not the kind of man who would go back on his words.
_______________________________________________________________
10. They first went to a large room that looked like a shop．
_______________________________________________________________
11. The man and the horse that fell into the river were drowned(淹死).
_______________________________________________________________
12.People who used horses to pull heavy loads would choose to keep stronger animals.
_______________________________________________________________
13.We write long letters in which we often discover our strangest selves.
_______________________________________________________________
14.One of the reasons that made it cool for him not to care was the power of his peer group.
_______________________________________________________________
15.The first interactions human had with horses were far different from those today.
_______________________________________________________________
16.I saw a woman running toward me in the dark. Before I could recognize who she was, she had run back in the direction from which she had come.
_______________________________________________________________
二.关系副词定语从句的整合与拆分
整合练习
1. I still remember the day. I first came to the school on the day.
(1)第一句为主句，第二句为从句，将两个单句合并为一句。
I still remember the day (I first came to the school on the day).
(2)重复的词是the day, on the day在从句中充当时间状语的成分，关系词中能作时间状语的词是when.
I still remember the day (when I first came to the school).
(3) when=on the day, 在定语从句中做时间状语，并连接先行词和定语从句。
2. The house has been pulled down. I lived in the house ten years ago.
(1)第一句为主句，第二句为从句，将两个单句合并为一句。
The house (I lived in the house ten years ago) has been pulled down.
(2)重复的词是the house, in the house在从句中做地点状语的成分，关系词中能作地点状语的词是where.
The house (where I lived ten years ago) has been pulled down.
(3) where=in the house, 在定语从句中做地点状语，并连接先行词和定语从句。
3. The reason is not clear. He refused the invitation for the reason.
(1)第一句为主句，第二句为从句，将两个单句合并为一句。
The reason (he refused the invitation for the reason ) is not clear.
(2)重复的词是the reason, for the reason在从句中做原因状语的成分，关系词中能作原因状语的词是why.
The reason (why he refused the invitation) is not clear.
(3) why=for the reason, 在定语从句中做原因状语，并连接先行词和定语从句。
另外关系副词when, where, why可以改为 ,介词 which, 介词取决于与先行词的搭配。
例如：
1.I still remember the day (when I first came to the school).
== I still remember the day (on which I first came to the school).
2.The house (where I lived ten years ago) has been pulled down.
==The house (in which I lived ten years ago) has been pulled down.
3.The reason (why he refused the invitation) is not clear.
==The reason (for which he refused the invitation) is not clear.
4. The box is full of bottles. He is standing on the box.
== The box on which he is standing is full of bottles.
The box where he is standing is full of bottles.
练习
1. This is the train. We work on the train.
---->_______________________________________________________
2. I know the reason. She did it for the reason.
---->_______________________________________________________
3. The man is our school master. You shook hands with the man just now.
----> _______________________________________________________
4. The pen is made in Shanghai. She is writing with the pen.
---->_______________________________________________________
5. Shanghai is the city. I was born in the city.
---->_______________________________________________________
6. This is the school where I studied a few years ago.
---->_______________________________________________________
7. Let’s go to the concert, where you will find much fun.
---->______________________________________________________
8. I still remember the day. I first came to the school on the day.
---->_____________________________________________________
9. Please tell me the reason.You are late for the reason.
---->_______________________________________________________
10. The reason is not clear. He refused the invitation for the reason.
---->______________________________________________________
分解练习
1.Dictionary is the only place where success comes before work.
---->_______________________________________________________
2.Defeat is a school where truth always grows strong.
---->_______________________________________________________
3.Courage is the ladder where all the other virtues mount.
---->_______________________________________________________
4.America is the country where I was born in the country.
---->_______________________________________________________
5. This is the reason why he is leaving now.
---->_______________________________________________________
6.There are thirty students in the class, most of whom are from the city.
_________________________________________________
7. He is the only person that was present at the time.
__________________________________________________
8. Please just tell me anything that you know about the author of the book.
__________________________________________________
9. He is no longer the simple-minded man that he was five years ago.
__________________________________________________
10. They hired two boats in which they came up to the source of the river.
________________________________________________________
经过这种整合与拆分练习后，对高考中语法填空和作文都很有帮助，同学们要好好练习！加油！
