摘要：定语从句是指在复合句中，修饰某一名词或代词的从句。被修饰的名词或代词叫先行词，定语从句一般紧跟先行词之后，由关系词（关系代词或关系副词）引出。

一、定语从句的定义

定语从句是指在复合句中，修饰某一名词或代词的从句。被修饰的名词或代词叫先行词，定语从句一般紧跟先行词之后，由关系词（关系代词或关系副词）引出。

二、定语从句的基本用法及举例

（一）关系代词who引导的定语从句，先行词是人，在从句中作主语。

1. The boy who is standing there is my brother.（站在那里的男孩是我的兄弟。）

2. I know the man who has a lot of knowledge.（我认识那个知识渊博的人。）

3. The teacher who teaches us English is very kind.（教我们英语的老师非常和蔼。）

4. She is the girl who likes reading books.（她就是那个喜欢读书的女孩。）

5. The woman who wears a red dress is my aunt.（穿红色连衣裙的女士是我的阿姨。）

（二）关系代词whom引导的定语从句，先行词是人，在从句中作宾语。

1. The man whom I met yesterday is my friend.（我昨天遇到的那个人是我的朋友。）

2. She is the girl whom we all like.（她就是我们都喜欢的那个女孩。）

3. I saw the boy whom you mentioned just now.（我看到了你刚才提到的那个男孩。）

4. The teacher whom he talked to is very experienced.（他与之交谈的那位老师很有经验。）

5. The woman whom they helped was very grateful.（他们帮助的那位女士非常感激。）

（三）关系代词which引导的定语从句，先行词是物，在从句中作主语或宾语。

1. This is the book which is very interesting.（这就是那本非常有趣的书，作主语）

2. The car which he bought last year is very expensive.（他去年买的那辆车很贵，作宾语）

3. I like the house which has a big garden.（我喜欢那座有大花园的房子，作主语）

4. She lost the pen which her mother gave her.（她弄丢了她妈妈给她的那支钢笔，作宾语）

5. The dog which is running in the yard is cute.（正在院子里跑的那只狗很可爱，作主语）

（四）关系代词that引导的定语从句，先行词既可以是人也可以是物，在从句中作主语或宾语。

1. The book that I read last night is very educational.（昨晚我读的那本书很有教育意义，先行词是物，作宾语）

2. The man that is talking on the phone is my father.（正在打电话的那个人是我的父亲，先行词是人，作主语）

3. She likes the dress that is very beautiful.（她喜欢那条非常漂亮的裙子，先行词是物，作主语）

4. The boy that we saw at the park is very naughty.（我们在公园看到的那个男孩很淘气，先行词是人，作宾语）

5. I found the key that I lost yesterday.（我找到了昨天丢失的钥匙，先行词是物，作宾语）

（五）关系副词when引导的定语从句，先行词是表示时间的名词，在从句中作时间状语。

1. I still remember the day when we first met.（我仍然记得我们第一次见面的那一天。）

2. He came at a time when I needed help most.（他在我最需要帮助的时候来了。）

3. The year when I graduated from university was 2020.（我从大学毕业的那一年是2020年。）

4. She left on the morning when it was raining heavily.（她在雨下得很大的那个早晨离开了。）

5. We had a good time during the holiday when we went to the beach.（我们去海滩的那个假期玩得很开心。）

三、定语从句专项训练单选题

1. This is the book ______ I bought yesterday.

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

2. The boy ______ is standing there is my classmate.

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

3. I like the movie ______ has a happy ending.

4. The man ______ you saw just now is our teacher.

5. The city ______ I visited last year is very beautiful.

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

6. She is the girl ______ mother is a doctor.

7. I still remember the day ______ we went to the zoo together.

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

8. The house ______ has a big yard is very expensive.

9. The book ______ cover is red is mine.

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

10. The man ______ I talked to is very friendly.

四、答案及解析

1. B。先行词是book（物），在从句中作宾语，所以用which。

2. B。先行词是boy（人），在从句中作主语，所以用who。

3. B。先行词是movie（物），在从句中作主语，所以用which。

4. C。先行词是man（人），在从句中作宾语，所以用whom。

5. A。先行词是city（物），在从句中作宾语，所以用which。

6. D。先行词是girl，从句中表示“女孩的妈妈”，所以用whose。

7. B。先行词是day（时间），在从句中作时间状语，所以用when。

8. A。先行词是house（物），在从句中作主语，所以用which。

9. C。先行词是book，从句中表示“书的封面”，所以用whose。

10. C。先行词是man（人），在从句中作宾语，所以用whom。

总结:定修名代。

来源：大明哥杂谈