郝昌明

定语从句是中学英语中的重要语法项目，先行词是定语从句中的重要组成部分，以先行词为突破口，可以巧妙学习定语从句。

一、认识先行词的重要性，初步了解定语从句结构

被定语从句所修饰的名词或代词叫先行词，没有了先行词，定语从句就失去了意义，也就失去了存在的必要，可见先行词是定语从句中不可或缺的重要内容。

例1：Is this factory ________ you visited yesterday？

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

析：C。分析语境含义和句子结构可知，this factory为主语，is为谓语，you visited yesterday为定语从句，但它缺少先行词，所以应填the one作先行词，以保持句子结构的完整性。

例2：The people who take an active part in sports prove healthier than ________ who don't.

A. / B. that C. those D. what

析：C。分析语境含义和句子结构可知，who don't为定语从句，但它缺少先行词，所以应填those作先行词，以保持句子结构的完整性。

二、弄清先行词的位置，进一步了解定语从句结构

因为定语从句修饰先行词，所以通常情况下先行词直接放在定语从句前面;但有时先行词不直接紧靠着定语从句，中间由一个定语、状语或谓语隔开。

例1：There is an expression in his eyes that I can't understand. 在他的眼睛里有一种我不明白的神情。

析：先行词an expression和定语从句被介词短语in his eyes隔开。

例2：The days are gone forever when the Chinese used foreign oil. 中国人民使用洋油的年代一去不复返了。

析：先行词The days被谓语are gone forever隔开。

三、弄清先行词由什么词担任，了解定语从句产生的背景

先行词既可指人也可指物，还可指一件事，通常由名词、代词或整个句子担任。了解了这一点，就了解了定语从句产生的背景。

例1：The girl who is standing there is my girlfriend. 站在那儿的女孩是我的女朋友。

析：先行词The girl为名词，指人。

例2：This book is the one I lost yesterday. 这是我昨天丢了的那本书。

析：先行词the one为代词，指物。

例3：A middle aged woman killed her husband， which surprised me. 一个中年妇女杀害了自己的丈夫，这一点令我很惊讶。

析：先行词为整个主句，指一件事。

四、认清先行词的作用，准确确定关系词

连接定语从句和先行词的词叫关系词，在定语从句中关系词代表着先行词。先行词在从句中的作用决定着关系词的选用;若先行词指人且在定语从句中作主语，可用关系代词who / that引导定语从句;若先行词指人且在定语从句中作宾语，可用who / whom / that引导定语从句，也可将who / whom / that省去;若先行词指物且在定语从句中作主语或宾语，可用that / which引导定语从句，作宾语时that / which可以省去;若先行词在从句中作定语，可用whose引导定语从句;若先行词在从句中作时间、地点和原因状语，可用when， where， why引导定语从句。

例1：Is this the girl who / that teaches us Chinese？ 这就是教我们语文的女孩吗？

析：先行词the girl在从句中作动词teaches的主语，应用who / that引导定语从句。

例2：This is the boy （who / whom / that） you met in the street yesterday. 这就是你昨天在街道上碰到的男孩儿。

析：先行词the boy在从句中作动词met的宾语，可用who / whom / that引導定语从句。

例3：He lives in a room whose windows are broken. 他住在一个窗子坏了的房间里。

析：先行词a room在从句中作从句主语windows的定语，应用whose引导定语从句。

例4：I still remember the days when I stayed in Beijing. 我仍然记得我在北京度过的日子。

析：先行词the days在从句中作时间状语，应用when引导定语从句。

例5：This is the room where he once lived. 这就是他曾经住过的房子。

析：先行词the room在从句中作地点状语，应用where引导定语从句。

例6：This is the reason why she was absent. 这就是她缺席的原因。

析：先行词the reason 在从句中作原因状语，应用why引导定语从句。

巩固练习：

1. The young man lifted the 250-kilogram stone at his first attempt， ________ surprised me greatly.

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

2. John， would you like to find me a chair ________ I can put these newspapers for a short time？

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

3. Let's go shopping together at five o'clock this afternoon， ________ our school will be over.

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

4. I hope to find an occasion ________ we can sit in our room to watch TV together.

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

5. I'm sorry that I can't think out a situation ________ these phrases appear at the same time.

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

6. Do you regret the time ________ you spent in playing computer games in that Internet Café？

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

7. In the opinion of me， the problem hasn't developed to the point ________ nobody of us can solve.

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

8. Is this knife ________ you cut your black pencil with a moment ago？

A. which B. that C. the one D. as

9. I just wonder whether this is the reason ________ she refused to come to help you yesterday morning.

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

10. To tell you the truth， I wouldn't like to accept the reason for your being late ________ you gave just now.

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

11. Can you see the girl dressed in a red skirt ________ is standing under a big tree over there？

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

12. This is the young man ________ you know I often help with his English.

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

13. Mary， would you like to show me the book ________ is a foreign woman？

A. whose writer B. writer of whom C. who's writer D. of whom writer

14. I wonder if this is the factory ________ you paid a visit to last week.

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

15. It is said that the company ________ produces Red Star cars in that city will be closed very soon.

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

16. I have already bought a large flat in a busy street ________ I will live in the rest of my life.

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

17. Can you remember the days ________ we stayed together on that mountain village？

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

18. The soldier ________ legs were badly wounded was operated on without delay.

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

19. I think that this is the office ________ we will hold this important meeting.

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

20. I think I can finish my homework at eight o'clock， ________ I'll have time to play with you.

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