时间：2022-03-15 02:03:37
[摘 要] 定语从句是高考英语命题的重中之重，更是学生理解和掌握的难点。怎样判定定语从句，选用什么样的引导词，怎样区分定语从句和同位语从句呢？灵活有效的方法是掌握这一知识点的关键所在。本文提供了简单而有效的学习方法。
[关键词] 定语从句 关系代词 关系副词
定语从句的定义：在主从复合句中，修饰句中的某一名词或代词的句子叫定语从句。被修饰的这一名词或代词叫做先行词，引导定语从句的词有关系代词和关系副词。
定语从句的分类：限制性定语从句(Restrictive Attributive Clause)和非限制性定语从句（Non-restrictive Clause）。定语从句的引导词有：关系代词who、whom(宾格)、whose(所有格)、that、which、as；关系副词when、where、why。
一、关系代词的用法
1. who先行词是人并在定语从句中作主语。如：The teacher who went to see me last night is Mr. Cao .（主语）I was the only person in my office who was invited. （主语）
2. whom先行词是人并在定语从句中作宾语(做及物动词的宾语或不及物动词加介词的宾语)。如：The boy whom I talked with just now will go to Shanghai.（介词宾语）
3.whose先行词可以是人也可以是物，whose是who的所有格形式，whose（adj.）+n (whose作定语) whose+名词可做主语或宾语。如：The doctor, whose name was Tom , lived in a small town in the north of China（主语）
4.that先行词既指人又指物，在从句中作主语或宾语或表语。如：He is no longer the man ( that ) he used to be .(表语)
5.which先行词是物并在从句中作主语或宾语。如：The apple which you gave him is eaten by me .(宾语)
二、关系副词的用法
关系副词when、wher、why在从句中作状语分别表示时间、地点、原因，也可用“介词+which”代替。
1.when先行词是表示时间的名词eg、time、year、day、week，但是，时间名词在句中作主语、宾语时，应用that/ which。如：I still remember the day (that/which) is his birthday.
2.where先行词是表示地点的词eg、house、room、place。如：This is the house where LuXun once lived. (where= in which)
3.why先行词（the reason）表原因。如：I know the reason why he came late.(why= for which)
三、限制性定语从句和非限制性定语从句
限制性定语从句是修饰限制先行词，缺少从句，句子意义不完整或失去意义，主从句关系十分密切，写时不用逗号分开。翻译成汉语只能是一个句子。如：This is a shop that sells personal computers.He came at a time when we needed him most.他是在我们最需要的时候来的。
非限制性定语从句只是对先行词作些附加说明，主从句关系不十分密切，如果去掉从句，主句的意思仍然清楚，这种从句和主句之间往往用逗号分开，一般用which ,不用that引导。译成汉语时，必须是两个句子。在非限制性定语从句中，有时根据句子意思，常把some、any、none、all、both、several、many、most、neither、either等词，分数或百分数与介词+whom/which连用。
四、介词+关系代词的用法
只有介词+whom/which不能用that。用什么介词由从句中的相关动词的习惯搭配决定，该介词通常可以放在关系代词之前，也可放在从句的末尾。如：The man whom I talked about at the meeting is from Beijing University. =The man about whom I talked at the meeting is from Beijing University. Great changes are taking place in the city in which they live.他们所居住的城市正在发生着巨大的变化。
定语从句也可以用“the + n + of +whom/which”，如：The house whose windows were damaged has now been repaired =The house the windows of which were damaged has now been repaired.窗子遭到破坏的那幢房子现在已经修理好了。
另外，固定词组的介词不能拆开用。介词也可结合句意和先行词确定。
关系代词的特殊用法：只用that引导定语从句的情况。
1.先行词是all、everything、something、anything、nothing、none、few、little、much等不定代词，或是被all、every、some、any、few、little等修饰时。如：Is there anything (that) I can do for you?
2.先行词被形容词最高级或序数词修饰时。如：This is the best film (that) I have ever seen.
3.先行词被the only、the very修饰时。如：He is the only person that is reliable.
4.先行词既有人又有物。如：They talked about the persons and things (that) they remembered in the school.
5.当主句是由who或which引导的特殊疑问句时，为了避免重复，定语从句用that。如：Who is the man that is standing by the door?
6.被修饰词是数词时，只用that。如：He brought two cats yesterday. now I can see the two that are playing in the garden.
7.如果两个从句，其中一个关系代词用which，另一个用that，以避免重复。如：He build up a factory which produced things that had never been before
此外，还有关系代词as引导的定语从句，本文不再赘述。
（作者单位：陕西省子洲县子洲中学）