定语从句用法小结（通用9篇）
篇1：定语从句用法小结
[定语从句的种类]
定语从句分为限制性和非限制性两种。限制性定语从句是句子不可缺少的部分，如去掉主句意思就不完整或失去意义；非限制性定语从句是先行词的附加说明，去掉也不会影响主句的意思。它与主句之间通常用逗号分开，一般不用that引导，关系词不可省略。如：
This is the book that I want to read. （限制性）
Tom’s father， who arrived just now， is a famous scientist. （非限制性）
非限制性定语从句的先行词成分可以是整个主句，非限制性定语从句常用which引导，修饰整个句子。定语从句的谓语动词要用第三人称单数。例如：
The weather turned out to be very good， which was more than we could expect.
关系代词引导的定语从句
关系代词所指代的先行词是表示人或物的名词或代词，并在句中充当主语、宾语、定语等成分。关系代词在定语从句中作主语时，从句谓语动词的人称和数要和先行词保持一致。
在定语从句中，who和that既可作主语又可作宾语，whom只可作宾语（作宾语时可以省略）。如：
Is he the man who/that wants to see you？ （who/that在从句中作主语）
The man （whom/who/that） you spoke to just now is our English teacher. （whom/who/that在从句中作宾语，可省略）
[whose]
在定语从句中作定语，可用来指人或物，表示物时相当于“the+名词+of+which”或“of+which+the+名词”。如：John， whose wife is ill， can’t come to the party.
[which & that]
which和that指代的先行词是表示事物的名词或代词，在定语从句中可作主语、宾语等。如：
Please show me the radio that/which you have just bought. （that/which在从句中作宾语，可省略）
This is the film that/which created a great sensation. （that/which在从句中作主语）
只能用that而不能用which的情况：
1. 先行词是最高级或被最高级修饰时。如：This is the best dictionary that I’ve ever used.
2. 先行词是序数词或被序数词修饰时。如：The first thing that we should do is to get some food.
3. 当先行词是anything， everything， nothing， something， few， all， none， little， some等不定代词时，或是由every， any， all， some， no， little， few， much等词修饰时。如：Tom told his father all that had happened.
There is little that I can do for you.
4. 先行词既有人又有物时。如：They talked about the teachers and the schools that they knew.
5. 先行词被the only，the very，the right等修饰时。如：This is the very book that I want to have.
6. 在which，who，whom引起的问句中，为避免重复。如：Who is the girl that talked to you yesterday？
7. 关系代词在定语从句中作表语时。如：China is not the country that it was.
只能用which，不能用that的情况：
1. 在非限制性定语从句中。如：Beijing， which is the capital of China， has a very long histroy.
2. 在介词后面，即“介词+which（指物）”。如：This is the house in which we lived three years ago.
[as]
关系代词as代替的先行词是人或物的名词， 在从句中作主语、宾语和表语。
as引导限制性定语从句时，常和such， the same， as（so）连用， 构成such ... as， the same ... as， as/so ... as等结构，在从句中可作主语、宾语和表语。如：
Don’t trust such men as praise you to your face. （在定语从句中作主语）
I have the same trouble as you have. （在定语从句作宾语）
It’s as pleasant a film as I have ever seen. （在定语从句作宾语）
但是当先行词被the same修饰时，that也可以引导定语从句，但意义有所不同。the same ... as（指同样或同类的）， the same ... that（指同一个）。例如：
This is the same watch as I lost.
This is the same watch that I lost.
as也可单独使用，引导非限制性定语从句，修饰整个主句或主句中的一部分，放在句首、句中或句末。如：
As is known to us all， smoking is harmful to one’s health. （指代整个主句，在从句中做主语）
He is late， as is often the case. （指代整个主句，在从句中做主语）
Light， as everybody knows， travels much faster than sound. （指代整个主句，在从句中做宾语）
as和which作关系代词的用法比较：
which引导的非限定性定语从句只能放在主句之后，which指代前面的一个句子或主句中的某一成分；as引导的非限定性定语从句能放在主句之前、中、后，既可指前面已经提到的情况，也可指后面提到的情况。
as引导从句时，有“为人所熟知”的含义，which则没有这层意思。as引导的从句往往表示的是一种附加说明，which引导的从句一般是较为重要的陈述。如：
His mother is ill， which makes him very sad.
As is expected， the England team won the football match.
[关系副词引导的定语从句]
关系副词when， where， why可代替的先行词是时间、地点或理由的名词，在从句中作状语， 相当于“介词+which”结构。例如：
I’ll never forget the time when/during which we worked in the factory.
This is the village where /in which he was born.
I don’t know the reason why/for which she looks unhappy today.
[判定用关系代词还是用关系副词]
关系代词与关系副词的选用，应看先行词在定语从句中充当什么成分：若作主语、宾语或定语，则用关系代词who，whom，that，which，whose，as等；若作状语， 就用where， when， why等关系副词。如：
The reason why I’m writing is to tell you about a party on Sunday. （状语）
The reason that/which he gave us sounded reasonable. （宾语）
Pisa is a city， which has a leaning tower. （主语）
Pisa is a city， where there is a leaning tower. （状语）
[介词+关系代词]
当关系代词作介词宾语时，就出现了“介词+关系代词”的结构引导定语从句的现象。当先行词指物时用“介词+which”，指人时用“介词+whom”，且关系代词不能省略。而这种结构中较难解决的问题是介词的选择问题：
1. 介词的确定可以根据整个句意来确定。
Oxygen is a kind of gas， without which we couldn’t live.
2. 介词可以根据与先行词的搭配来确定。
He gave me the book for which he paid a lot of money. （动词与介词搭配）
1949 was the year in which the P.R.C. was founded. （名词与介词搭配）
The snake， of which she used to be afraid， is her favorite animal now. （形容词与介词搭配）
★ 浅谈定语从句
★ 从句讲解定语从句 (人教版高三英语下册教学论文)
★ 定语从句练习题
★ 定语从句课件
★ 英语的定语从句的句子总结
★ 定语从句例句名言
★ 定语从句教学反思
★ 初中英语定语从句教案
★ 定语从句的课件
★ 大学英语四级考试语法：—定语从句
篇2：定语从句用法小结
江泽珍
1、语言知识目标：记住定语从句定义和定语从句的结构，掌握关系代词和副词的使用。
2、语言技能目标：能够在听说读写中熟练使用定语从句。
3、情感态度目标：在学习中培养合作精神。
4、学习策略目标：学会总结所接触的语言材料中的语言规律并加以应用。教学重点：
定语从句的结构及关系代词和关系副词的使用。介词+关系代词的考查。教学难点：
1、关系代词和关系副词在从句中充当的成分。
2、先行词是地点名词、时间名词及reason 时，关系代词和关系副词的选择。
3、as 的用法以及对定语从句的综合考查
教学方法： 以学生为主体的发现学习和合作学习
教学辅助手段：多媒体教学 教学过程：
Step 1: Revision Check the homework exercises.Step 2: Leading in Show some pictures of our beautiful school and give two simple sentences, and then combine the two sentences using the Attributive Clause.Step 3: To review the basic knowledge of the Attributive Clause 归纳总结：
指代人 who, whom, that, as 关系代词 指代事物 which, that, as 关系代词 所属关系 whose 关系代词 指地点 where（=介词+which）关系副词 指时间 when(=介词+which）关系副词 指原因 why(=for+which）关系副词 限定性定语从句与非限定性定语从句
Step 4: Summary for testing points ,difficult points and exercises.考点：1.that与which 2.对the way的考查 3.介词+关系词 难点：4.as的使用 5.对where的考查 6.综合考查
Step 5: Grammar practice and consolidation.Step 6: Ability to enhance Our class is a big family;It consists of 50 girls and 18 boys.Most of us are mainly from the countryside.Cao Yichun is a kind-hearted boy.He is always ready to help others.He is such a good boy that we all like him.Step 7: Summary Step 8: Homework Do more exercises about the Attributive Clause.课后反思：
（1）时间把握得比较好，就是训练效果需要再加强。
篇3：As在定语从句中的用法浅析
一、引导限制性定语从句
1、在限制性定语从句中, as多和such和the same连用, 构成“such…as”和“the same…as”结构, 可以代替先行词是人或物的名词, 在从句中充当主语、宾语或表语。
例1.I've never seen such a talented young man as he is. (“as”作表语)
例2.Such books as I have read are classical works. (“as”作宾语)
例3.I don't like such a man as talks big. (“as”作主语)
2、such…as与such….that的区别。
例4.He is such a good teacher as every student likes.
(“as”引导定语从句并在从句中充当宾语)
例5.He is such a good teacher that every student likes him.
(“that”引导结果状语从句, 从句中不缺少成分)
3、另外, the same…as虽然在结构上与the same…that相同, 有时句意却不一样。
例6.This is the same wallet as I lost the other day.
这个钱包和我几天前丢的那个一模一样。
例7.This is the same wallet that I lost the other day.
这正是我前几天丢的那个钱包。
但如果先行词表示抽象概念, 则没有这种区别。如:例8.She told me the same story as (that) she had told you.
4、as还可以用在so和as之后, 构成“so…as, as…as”结构这种结构前面的so或as是副词, 后面的as是代词。如:
例9.Here is so difficult a question as nobody can answer.
例10.He is as great a painter as ever lived.
二、引导非限制性定语从句
在非限制性定语从句中, as作为关系代词代替整个句子。As引导的从句位置较灵活, 可以位于主句前面、中间或后面, 一般用逗号与主句隔开, 通常译为“ (正) 如……一样”。关系代词as用于引导非限制性定语从句时, 应注意其用法上与which的异同。
1、相同点
(1) as和which都能引导定语从句, 并都可以在定语从句中做主语或宾语, 代表前面整个句子。
例11.More American troops are being sent to the middle East which (as) I have learnt from the newspaper.
例12.He married her, as (which) was natural.
(2) 当非限定性定语从句位于句末时, 多数情况下as和which都可用来引导这个定语从句。
例13.The number of senior high school students is increasing, as is mentioned above. (as引导非限定性定语从句, 意思是“正如”。此时也可以换用which引导, 但意思有别, 意思是:“这一点上面提到了”。)
但是, 当主句是否定句时, as和which就不能互换, 因为as引导的非限制性定语从句不包含否定意义。
例14.Spiders are not insects, as many people think.
蜘蛛不是昆虫, 而许多人却认为蜘蛛是昆虫。
2、不同点
(1) 语义上的区别
As作为关系代词仍多少保留“理由”“比较”“方式”“等同”等意义, 而which没有这些意义。因此, 由as引导的定语从句通常在意义上不可与主句相悖, 而且一般是肯定的, 对主句意义起相辅作用, 表示“正如”等意义;而which引导从句则不受此限制。
例15.Mother treats me just like a baby, which I can’t bear.
例16.She has married again, which was unexpected.
(上面两句中的which都不宜用as。)
(2) 用法上的区别
which只能放在主句后面, 而as引导的从句位置相对比较灵活, 可以放在前, 也可以放在后, 甚至还可以分割主句。另外, as常常有“正如、正像”的含义。
例17.As might be expected, John was admitted to the university. (在前)
例18.Air, as we know, is a gas. (在中)
例19.He was a foreigner, as I know from his accent. (在后)
在as引导的定语从句中, as后若为is或was+过去分词构成的被动语态, is或was可省掉。而which后面若是这种情况, 则不可以省略。
例20.The material is elastic, as (不用which) shown in the figure.
例21.As (was) planned, we met at the airport. (可省略was)
which在句法上常用作实意动词的主语, 这时它所引导的从句与主句之间常含有并列、因果关系, 可以用and this, and that代替, 意思是“这件事”。而as主要起与上下文连接的作用, 表达说话人的看法、观点, 并指出主句内容的出处或根据等。
例22.I bought my brother a big toy, which (=and that) delighted him greatly.
例23.Einstein, as we know, is a famous scientist.
在从句中作介词宾语时, 要用which, 不能用as。如:
例24.She might possibly come, in which case I’ll ask her.
例25.There is a great deal of oxygen around us, without which we could not live.
在句法上, as常用作一些实意动词 (如see, know, hear, remember, say, report, show, expect, guess等) 的宾语, 译为“正如、象、由……而知、与……一致”。这类动词与as几乎成了一种固定搭配。
例26.Shakespeare is a famous writer, as we all know.
当从句的谓语动词是否定形式或从句谓语动词带的是一个复合宾语结构时, 一般用which而不宜用as。
例27.You pretended not to know me, which I didn’t understand.
例28.He admires everyone in the class, which I find quite strange.
as引导的定语从句有其一定的复杂性, 我们只有不断学习, 不断研究, 在实践中不断去体会, 才能做到恰当运用。
摘要：As一词有多种用法, 其中一个重要用法就是它可用作关系代词引导定语从句, 既能引导限制性定语从句, 又能引导非限制性定语从句。本文旨在此方面作一探述。
关键词：as,关系代词,限制性定语从句,非限制性定语从句
参考文献
[1]吉晓静.关于定语从句的教学探讨[J].陶瓷研究与职业教育, 2005, (01) .
[2]吴廷军, 王海燕.限制性与非限制性定语从句的区别[J].中学文科, 2006, (06) .
[3]郭著章, 李庆生.英汉互译教程[M].武汉:武汉大学出版社, 2003.
篇4：定语从句中关系词的选择用法小结
定语从句中选择关系词的唯一依据是看关系词所代指的先行词在定语从句中充当什么成分。而不是看先行词是什么词性。
1. 如果作主语或动词的宾语，则选用关系代词，如果作状语，则选择相应的关系副词。
例如：
① He worked in the factory which produces TV sets.
② He worked in the factory where his father had worked.
句①中先行词the factory在定语从句中作主语，所以用关系代词which，句②中先行词the factory在定语从句中作地点状语，所以用where。
2. 选用关系词的方法：一“找”二“还”三“替换”
找：就是先把句子分为主句和从句两部分，再找出先行词（定语从句所修饰的词）和关系词（连接定语从句和先行词的词）。
还：根据先行词提示的意思，大胆地把定语从句还原为完整的一句话。（可以适当添词）
替换：用关系词替换定语从句中还原后添加的部分，作主语和宾语用关系代词，作状语用关系副词。（时间状语用when，地点状语用where， 原因状语用why）。
例如：
① This is the school I once studied.
② This is the school is the most famous in the city.
找：根据句意和句子结构，确定先行词为the school。需要填入的则是连接先行词和后面从句的关系词。
还原：根据先行词的提示，这两句话的定语从句还原成完整的一句话后分别为：
I once studied at the school.
The school is the most famous in the city.
（斜体部分为根据先行词的意思把关系词还原后的部分）
替换：根据还原后的句意，句①中先行词the school在定语从句中作地点状语，所以用where， 句②中先行词the school在定语从句中作主语，所以用which / that。
二、“介词+关系代词”引导的定语从句
1. 当关系代词在定语从句中作介词的宾语时，应用“介词+关系代词”的结构，如果指人，用“介词+whom”；如果指物，用“介词+which”。介词后面的关系代词 which， whom 不能省略，也不能被that， who 代替。例如：
① Do you like the book for which I paid 20 dollars？
你喜欢我付了20美元买的那本书吗？
② Mr. Smith is a teacher from whom I have learnt a lot.
史密斯先生是一个让我从他身上学到好多东西的老师。
2. 在定语从句中，介词也可以放在定语从句的后面，此时作宾语的关系代词which， whom 可以被that 或者 who 替换，也可以省略。例如：
① Mr. Jason is a kind person with whom I talked just now.
= Mr. Jason is a kind person （whom / who） I talked with just now.
② The book in which I am interested is Harry Potter.
= The book （which / that） I am interested in is Harry Potter.
3.“介词+关系代词”中介词的选择
1） 根据定语从句中的动词或形容词与介词的搭配确定。
The West Lake， for which Hangzhou is famous， is worth visiting.
2） 根据先行词和介词的搭配来确定。
Tom lives in a big house in which there is a cherry tree.
3） 根据定语从句所表达的意思来确定。
Water， without which man cant live， has been seriously polluted.
4） 表示“所属关系”或“整体与部分”关系时，用介词of，形式通常为：名词、不定代词或数词+of+which / whom.
I sent him a good book， the name of which is Gone with the Wind.
5） 当先行词是way且在从句中作状语时，用 in which 或 that 引导定语从句，通常 in which 或 that 可省略。
I dont like the way （that / in which） he spoke to his parents.
三、巩固练习
1. This is the house I lived when I was young.
A. whichB. that
C. in whichD. as
2. Jane is my best friend I borrowed an Apple Watch， and I have kept it for three weeks.
A. from whichB. from whom
C. to whichD. to whom
3. The house I grew up has been taken down and replaced by an office building.
A. in itB. in
C. in thatD. in which
4. Is this the reason he explained at the meeting for his carelessness in his work？
A. thatB. what
C. howD. why
5. Is this the reason he was so careless in his work？
A. thatB. what
C. howD. why
6. The reason he didnt come was he was ill.
A. why； thatB. that； why
C. for that； thatD. for which； what
7. He lives in a village is not far from the city.
A. whichB. where
C. whatD. whose
8. He lives in the village he was born.
A. whichB. where
C. whatD. whose
9. In an hour， we travel to places could have taken our ancestors days to reach.
A. whereB. when
C. whichD. what
10. In an hour， we travel to places we can relax and get refreshed.
A. whereB. when
C. whichD. what
11. Ill never forget the days we spent together.
A. thatB. /
C. whenD. A and B
12. I am looking forward to the day my daughter can read this book and know my feelings for her.
A. asB. why
C. whenD. where
13. If we want to have a bright future， we must learn to act in ways do not do harm to other living things.
A. in whichB. /
C. howD. that
14. Is this the factory color TV sets are produced？
A. whenB. the one where
C. thatD. in which
15. Is this factory color TV sets are produced？
A. whichB. the one where
C. thatD. in which
参考答案
1—5 CBBAD6—10 AABCA11—15 DCDDB
篇5：as定语从句用法总结参考
一、as引导定语从句
as引导定语从句时，既可以引导限定性定语从句，又可以引导非限定性定语从句。区分as引导定语从句和其它从句的关键特征是：as引导定语从句时在从句中做成分，通常做主语或宾语。
1、as引导限定性定语从句
如从句所修饰的名词前有such、the same、as出现，后面的定语从句将由as引导，形成such...as，the same...as，as…as这样的固定结构，译为“和……一样”。
例1：I never heard such stories as he told.
我从未听过他所讲的那样的故事。
例2：He’ll repeat such questions as are discussed in the book.
他将重复书中讨论过的问题。
例3：They made the same mistake as others would have made on such an occasion.
他们犯了和其他人在这种场合下会犯的同样错误as用法详解as用法详解。
2、as引导非限定性定语从句
as引导非限定性定语从句，往往指代一整句话，通常表示“正如”的意思。as引导的非限制性定语从句位置相对比较灵活，可以位于先行词之前、之后或中间。
例：As is known to everybody, the moon travels round the earth.
众所周知，月亮绕着地球转。
二、as引导时间状语从句
as引导时间状语从句多用于口语，强调“同一时间”或“一先一后”，有时还有“随着”的含义。
例1：As I was going out, it began to rain.
当我出门时，开始下雨了。(as强调两个动作紧接着发生，不强调下雨的.特定时间。)
例2：As time goes on, he will understand what I said.
随着时间的推移，他会理解我所讲的话。
三、as引导原因状语从句
as表示“因为”，与because相比，较口语化，所表达的原因语气较弱，所表的原因比较明显，或是已知的事实。
例1：As the weather is so bad, we have to delay our journey.
因为天气太糟糕，我们不得不推迟旅行。
例2：Any new source of energy will be very welcome, as there is already a shortage of petroleum.
任何新型能源都将大受欢迎，因为石油已经出现短缺。
四、as引导方式状语从句
as表示“按照”，“以……方式”，“像……一样”，“正如”。
例：Do as the Romans do when in Rome. 入乡随俗
注：as在引导方式状语从句时，还常出现在一个固定的类比结构中：(just) as …, so…。这一句型表示类比，基本含义是“正如……，所以……”。
例：Just as virtue is its own reward, so is vice its own punishment.
善有善报，恶有恶报。
五、as引导让步状语从句
as可以表示“尽管”，“虽然”，引导让步状语从句，但必须构成倒装。让步状语从句倒装规则有两类：
1、形容词/副词/分词/名词(无冠词)/介词短语等+as+主语+谓语动词，主句。
例1：Much as I like you, I couldn’t live with you.
我尽管很喜欢你，却不能和你在一起生活。
例2：Child as he is, he knows to help others.
尽管他是个孩子，他懂得帮助别人。
2、动词原形+as+主语+助动词(may/might, will/would, can/could, do/does/did)，主句as用法详解考研英语。
例：Try as we may, we cannot sense directly the television signal sent out from the broadcast station.
尽管我们费了很大的劲，也无法直接觉察发射台发出的电视信号
六、as引导比较状语从句
as引导比较状语从句，其基本结构是as…as。前一个as是副词，后一个as是比较状语从句的连词。否定结构为not so much … as …。
例1：Small as it is, the ant is as much a creature as are all other animals on the earth.
尽管蚂蚁很小，但是它同地球上的任何其他动物一样，也是一种动物。
例2：It was not so much the many blows he received as the lack of fighting spirit that led to his losing the game.
篇6：定语从句as的用法课件
as作连词，常用来连接主句和状语从句。
1.引导时间状语从句，作“当...的时候”解，有“随着...”之意，与while意义相近，强调两个动作同时发生;或某事一发生，另一事立即发生。eg：
He shouted aloud as her ran along.他一边往前跑，一边高声地呼喊。
I was startled as he opened the door.他一开门，我吓了一跳。
as作连词，相当于when。eg;
As a little boy (When he was a little boy)he began to learn to play piano.他小时候就开始学弹钢琴。
2.引导原因状语从句，作“因为，由于”解，与because的用法相近。eg;
I must stop writing now，as I have rather a lot of work to do.我必须停笔了，因为我还有许多工作要做。
3.引导方式状语从句或比较状语从句，作“正如，(如)像”解。例eg：
As in your country，we grow wheat in the north and rice in the south.正如(像)你们国家一样，我们在北方种小麦，在南方种大米。(方式状语从句)
When at Rome，do as Romans do.入乡随俗。(方式状语从句)
4.引导让步状语从句，作“虽然，尽管”解。这时从句常用倒装语序，即把从句中的表语、状语或动词原形放在as之前。eg;
Strange as it may seem，it is true.尽管这事看上去很奇怪，但却是真的。
Try as he might，Tom could not get out of the difficulties.不管怎样努力，汤姆还是摆脱不了困境。
篇7：非限制性定语从句的用法讲解
在我校当时有100学生，他们都很会唱英文歌。
(表明“我校当时只有100个学生”。)
作者|丹丹英语
公众号：英语语法学习
篇8：定语从句用法小结
例如:
1.It’s about a time when there were black slaves in North America. (when的先行词为time (时间名词) , when作状语, 相当于during the time。)
2.As a child he used to work hard and helped his father on the small farm where they lived. (where的先行词为the small farm, where相当于on the small farm。)
3.Can you tell me the reason why he didn’t attend the meeting last week? (why的先行词一定是the reason。)
关系副词when、where、why在定语从句中的用法必须注意两点:1) 关系副词的先行词必须是时间名词、地点名词和原因;2) 关系副词一定是作状语的。所以如果不具备这两个条件, 就不能用关系副词where、when、why, 而要用关系代词which/that。
请比较下面的句子, 会有所启发:
1.I’ll never forget the days when we studied together. (when关系副词, 作状语, 相当于during the days;studied在这里为不及物动词, 不接宾语, 因为我们不能说“学习日子”。)
2.I’ll never forget the days which we spent together. (which关系代词, 相当于the days, 作spend的宾语, 因为spend是及物动词, 要带宾语。)
3.This is the house where we used to have meals. (where关系副词, 作状语, 相当于in the house;所引导的定语从句是个主谓宾结构, 故不需要关系代词去充当主语或宾语。)
4.This is the house which I bought three years ago. (which关系代词, 相当于the house, 作及物动词buy的宾语。)
5.Do you understand the reason why she felt sad? (why关系副词, 作状语, 相当于for the reason;所引导的定语从句是个主系表结构, 故不需要关系代词去充当主语。)
6.Do you understand the reason that she explained to you? (that关系代词, 相当于the reason, 作及物动词explain的宾语。)
巩固练习:
将关系词when, where, why, which/that填入下列各句中。
1.I still remember the days_____ we worked together.
2.This is the sitting-room _______I used to sit in the evening.
3.This is just the place__________ I have been expecting to visit for all these years.
4.Winter is the time of year________ the days are short and nights are long.
5.I often think of my childhood_________ I think was very happy.
6.Beihai Park is a beautiful park in Beijing, _________was built about 300 years ago.
7.This is the reason _________his father left the factory angrily.
8.This is the factory_________ his brother worked ten years ago.
9.She would never forget the night__________ she lost the necklace.
10.I still don't understand the reason__________ my friend Li Ming explained to me yesterday.
参考答案:
篇9：浅析定语从句的用法
1. 作为引导词；
2. 指代或替代先行词；
3. 在定语从句中充当一个成分。
关系词又分为关系代词和关系副词。关系代词起着代词和连词的作用，关系副词起着副词、介词短语或连词的作用。关系代词有that、which、who、whom、whose、as等；关系副词有when、where、why等。
在学习定语从句时，同学们往往感到很困惑，不能真正理解定语从句的结构，无法正确判别关系词，从而影响答题的正确率。下面, 笔者将会结合高考试题，说明定语从句和强调句、同位语从句、主语从句以及宾语从句的区别，着重分析关系词的判别，以帮助同学们审题、辨析，从而正确答题。
定语从句与其他句型的区别
英文中的某些句型，如强调句、同位语从句、主语从句以及宾语从句等，和定语从句有很多相似之处，同学们难以准确判断、正确区分。如何正确区分定语从句和其他句型呢?
与强调句的区分
强调句最为显著的结构特征就是“It is/was...that/who/whom...”。先把“It is/was...that/who/whom...”去掉，在不增加或减少任何单词的情况下，如果句子结构完整则为强调句，否则就有可能是定语从句。例如：
例1. It is the playground ____ he picked up my package.
A. thatB. whereC. whenD. as
分析：答案选B。如果将“It is... ____ ”去掉，句子的剩余部分为“the playground he picked up my package”，句子结构不完整，因此判定该句不是强调句型，排除that。句子的中心词是“the playground”，表示地点，后面的从句是用来修饰限定名词playground，因此是定语从句，故选择表示地点的关系副词where来引导。
例2. It was after he got what he had desired ____ he realized it was not so important. (2006 辽宁)
A. thatB. whenC. sinceD. as
分析：答案选A。如果将“It was... ____ ”去掉，句子的剩余部分为“after he got what he had desired he realized it was not so important”，句子结构仍然完整，因此判定此句为强调句型，被强调的部分是一个时间状语，所以选that。
与同位语从句的区分
区分同位语从句和定语从句的关键在于：
1. 从句的作用不同。定语从句具有形容词或副词的特点，对先行词起修饰、限定作用，描述先行词的性质或特征，与先行词之间是所属关系。同位语从句具有名词的特点，对中心词作进一步补充解释，是中心词的具体内容。
2. 先行词不同。同位语从句所修饰的先行词通常是一些表示抽象意义的名词，而定语从句的先行词没有这个限制。
3. 连接词的作用不同。连接同位语从句的that只起连接作用，不在从句中担任任何句子成分。What、whether和how可以引导同位语从句，但不能引导定语从句。而定语从句中的关系词除了连接从句的作用外，还必须充当一定的句子成分。例如：
例1. He collected the facts ____ proved the earth moves around the sun.
A. ifB. whenC. that D. which
分析：答案选C/D。此句的先行词是“the facts”，从句“____ proved the earth moves around the sun”是对先行词的修饰和限定，且fact不是抽象意义的名词，因此判断该句是定语从句，而从句中缺少主语，需要一个引导词充当主语。因此选择that/which作定语从句的主语。
例2. A warm thought suddenly came to me ____ I might use the pocket money to buy some flowers for my mother's birthday. (2006 安徽)
A. ifB. whenC. thatD. which
分析：答案选C。从句“I might use the pocket money to buy some flowers for my mother's birthday”是对主语“a warm thought”的进一步补充解释，是“thought”的具体内容，且从句内部不缺少任何句子成分，从而判断该句是同位语从句，这四个选项中只能选that引导。
与主语从句的区分
定语从句与主语从句的区别是：定语从句在句中作定语，而主语从句在句中作主语。主语从句中的that只起引导主语从句的作用，不担任任何成分；定语从句中的that可以担任成分(如主语或宾语等)。例如：
例1. ____ is known to everybody, the moon travels round the earth once every month. (2001全国)
A. ItB. AsC. That D. What
分析: 答案选B。句中的主语是“the moon travels round the earth once every month”，不缺主语，所以判断“____ is known to everybody”不是主语从句。它在句中作定语，且用逗号与主句分隔，因此该句是非限定性定语从句，不能用that引导。而从句中缺少主语，因此使用as作从句的主语，指代后面的整个句子。
例2. It surprised all the people ______ such a little child made me recognize what silly mistakes I had made. (2005 湖南)
A. that B. who C. whoseD. whom
分析：答案选A。该句中，it是形式主语，“surprised”是谓语，“all the people”是宾语，因此从句“such a little child made me recognize what silly mistakes I had made”才是真正的主语，因此判断该句是主语从句而非定语从句。选择that引导主语从句，且that在从句中不担任任何成分。
与宾语从句的区分
宾语从句作谓语动词的宾语，若由that引导，that只起连接作用而不作句子成分；定语从句中的that作句子成分(如主语或宾语等)。例如：
例 1. If you are traveling together with me, please tell my third daughter something ______ we might get during the trip.
A. whatB. whose C. who D. that
分析：答案选D。本题考查的是一个双宾语结构，即“tell sb. sth.”。题干中的“my third daughter”为tell的间接宾语；“something”为tell的直接宾语，两个宾语都具备，因此判断从句不是宾语从句，而是修饰“something”的定语从句，且get为及物动词，需要接宾语。因此选择that引导定语从句，并作及物动词get的宾语。
例 2. If you are traveling together with me, please tell my third daughter ______ a friend of hers will look after me very well.
A. suchB. whose C. who D. that
分析：答案选D。本题考查的仍然是“tell sb. sth.”这个双宾语结构，具备了间接宾语“my third daughter”，可是缺少了一个直接宾语sth.，从而判断从句是宾语从句。但是从句中不缺少任何成分，因此选that作引导词，只起连接作用。
关系词的确定
根据限定性定语从句和非限定性定语从句的要求来确定
限定性定语从句非限定性定语从句
句意紧凑，主从句之间没有逗号句意较为松散，主从句之间必须有逗号隔开
可以用that作为引导词不可用that，只可用which或as等
关系代词作宾语时可以省略关系代词作宾语时不可以省略
whom可以用who替代whom不可以用who替代
我们不妨借助下面这个口诀进行记忆：
非限从句五要点：逗号、which是关键；
As、which功劳大，从句位置较随便；
宾语成分不能省，who与whom替代免。
高考中，涉及非限定性定语从句的考点经常会考查as 和which的用法，这两个词在引导非限制性定语从句时，都可以指代主句所表达的整个意思，且在定语从句中都可以作主语和宾语。不同之处主要有两点：
1. As 引导的定语从句可以置于句首，而which引导的不可以。
2. As 代表前面的整个主句并在从句中作主语时，从句中的谓语必须是系动词；若从句中的谓语是行为动词，则从句中的关系代词只能用which。
例1. Her sister has become a lawyer,______ she wanted to be. (2005 湖北)
A. who B. that C. whatD. which
分析：答案选D。根据以上口诀，题干中有逗号，可知题中“ ________________ she wanted to be”是一个非限定性定语从句，因此首先排除that；再排除what，因为what不能用来引导定语从句；然后依据先行词“a lawyer”，指代“律师”这个职业，所以，用which来指代sth.。
例 2. _____ I explained on the phone, your request will be considered at the next meeting. (2005 浙江)
A. WhenB. AfterC. AsD. Since
分析：答案选C。As作为关系代词，表示“正如……一样”，指代后面整个主句，as在从句中作explain的宾语。As引导定语从句时，既可放在句首，也可放在主句之后。Which虽然可以引导非限制性定语从句，但它不能置于句首。
例 3. The owner of the cinema needed to make a lot of improvements and employ more people to keep it running,______ meant spending tens of thousands of pounds. (2006 江苏)
A. whoB. that C. as D. which
分析：答案选D。根据口诀可知，本题考查非限定性定语从句。而在非限定性定语从句中，是不能使用that的。As引导定语从句，代表前面的整个主句并在从句中作主语时，从句中的谓语必须是系动词；若从句中的谓语是行为动词，则从句中的关系代词只能用which。
根据关系词在从句中充当的成分来确定
要确定定语从句中的关系词，就需要首先明确关系代词和关系副词在从句中的不同作用。
关系代词who、that、which、as在定语从句中作主语，或在及物动词或介词后作宾语；关系代词whose在定语从句中作定语；关系副词when、where、why在定语从句中作状语。
例 1. Do you still remember the chicken farm _____ we visited three months ago? (2005北京春)
A. where B. when C. that D. what
分析：答案选C。句中“_____ we visited three months ago”是定语从句，修饰表示地点的名词词组“the chicken farm”。虽然先行词是表示地点的名词，但visit是及物动词，因此定语从句中缺少宾语， 则必须用that或which在从句中作及物动词visit的宾语，而不能用关系副词。
例2. —Where did you get to know her?
—It was on the farm ______we worked. (2007山东)
A. thatB. thereC. which D. where
分析：答案选D。在定语从句“ ______ we worked”中，worked是不及物动词，后面不需要跟宾语，应选择表示地点的关系副词where引导定语从句，where在从句中作地点状语，代表“on the farm”。
例3. George Orwell, ______was Eric Arthur, wrote many political novels and essays. (2004北京)
A. the real nameB. what his real name
C. his real nameD. whose real name
分析: 答案选D。在题中，“ ______was Eric Arthur”是非限定性定语从句，“whose real name”作定语从句的主语；whose相当于“George Orwell's”，修饰“real name”，在从句中作定语。
根据固定搭配来确定
英语句型中经常有一些固定搭配：如“such...as...”“the same...as...”“as...as...”等。另外，as还有在非限定性定语从句中指代整个主句的一个用法特征，这些特征也能帮助我们确定定语从句的关系词。
例 1. Such machines ______ are used in our workshop are made in China. (2004江苏)
A. which B. whenC. whatD. as
分析：答案选D。句中“such...as...”是一个固定搭配，as作为关系代词指代“the machines”，且as在定语从句作主语。
例 2. I wanted the same shirt ______ my friend's, ____ surprised everybody in the office. (2005 浙江)
A. as; which B. of; thatC. as; it D. which; as
分析：答案选A。由固定搭配“the same...as...”判断第一个空格处填as；第二个空格显然是一个关系词来指代整个主句，而从句前有逗号隔开，为非限定性定语从句，用which。
定语从句的内容比较丰富，同学们除了掌握上述关系词的用法之外，还必须进一步理解和领悟其他关系词的用法，切实把握定语从句的结构，才能不断提高我们的解题能力和英语水平。
真题演练
1. His movie won several awards at the film festival, _____ was beyond his wildest dream. (2007上海)
A. whichB. thatC. whereD. it
2. Those successful deaf dancers think that dancing is an activity ____ sight matters more than hearing. (2007天津)
A. whenB. whoseC. whichD. where
3. Human facial expressions differ from those of animals in the degree ____ they can be controlled on purpose. (2007重庆)
A. with which B. to which C. of which D. for which
4. Eric received training in computer for one year, _____ he found a job in a big company. (2007辽宁)
A. after that B. after which C. after it D. after this
5. The village has developed a lot ____ we learned farming two years ago. (2007福建)
A. whenB. whichC. thatD. where
6. By serving others, a person focuses on someone other than himself or herself, ____ can be very eye-opening and rewarding.(2007湖南)
A. whoB. whichC. whatD. that
7. The book was written in 1946, ____ the education system has witnessed great changes.(2007山东)
A. when B. during which
C. since thenD. since when
8. Last week, only two people came to look at the house, ____ wanted to buy it. (2007安徽)
A. none of them B. both of them
C. none of whom D. neither of whom
9. It is reported that two schools, ____ are being built in my hometown, will open next year.(2007四川)
A. they both B. which both
C. both of themD. both of which
10. Today, we'll discuss a number of cases ____ beginners of English fail to use the language properly. (2007陕西)
A. whichB. asC. whyD. where