1、 定语从句在句中作定语，修饰名词或代词，被修饰的名词词组或代词即先行词。定语从句通常出现在先行词之后，由关系词（关系代词或关系副词）引出。关系代词有：who,whom, whose, that, which 等。关系副词有：when, where, why 等。1 关系代词引导的定语从句关系代词所代替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。1）who, whom, that 这些词代替的先行词是表示人的名词或代词，在从句中作主语或宾语。例如：Is he the man who/that wan
2、ts to see you?他就是你想见的人吗？（who/that 在从句中作主语）He is the man whom/that I saw yesterday.他就是我昨天见的那个人。（whom/that 在从句中作宾语）2）whose 用来指人或物（只用作定语，若指物，它还可以同 of which 互换）例如：They rushed over to help the man whose car had broken down.那人的车坏了，大家都跑过去帮忙。Please pass me the book whose (of which) cover is green.请递给我那本绿皮的书
3、。3）which, that 所代替的先行词是表示事物的名词或代词，在从句中可作主语、宾语等。例如：A prosperity which/that had never been seen before appears in the countryside.农村出现了前所未有的繁荣。（which/that 在句中作宾语）The package (which/that) you are carrying is about to come unwrapped.你拿的包快散了。（which/that 在句中作宾语） 2 关系副词引导的定语从句关系副词可代替的先行词是表示时间、地点或理由的名词，在从句中
4、作状语。1）关系副词 when, where, why 的含义相当于“介词+which“结构，因此常常和“介词+ which“结构交替使用。例如：There are occasions when (on which) one must yield.任何人都有不得不屈服的时候。Beijing is the place where (in which) I was born.北京是我的出生地。Is this the reason why (for which) he refused our offer?这就是他拒绝我们帮助他的理由吗？2）that 代替关系副词，可以用于表示时间、地点、方式、理由的
5、名词后代替 when, where, why 和“介+which”引导的定语从句，在口语中 that 常被省略。例如：His father died the year (that/when/in which) he was born.他父亲在他出生那年逝世了。He is unlikely to find the place (that/where/in which) he lived forty years ago.他不大可能找到他四十年前居住过的地方。3 判断关系代词与关系副词方法一：用关系代词还是关系副词完全取决于从句中的谓语动词。及物动词后面无宾语，就必须要求用关系代词；而不及物动词则要
6、求用关系副词。例如：This is the mountain village where I stayed last year.这是我去年呆过的山村。Ill never forget the days when I worked together with you.我永远不会忘记与你共事的日子。判断改错：（错）This is the mountain village where I visited last year.（对）This is the mountain village (which) I visited last year.（错）I will never forget the da
7、ys when I spent in the countryside.（对）Ill never forget the days (which) I spent in the countryside.习惯上总把表地点或时间的名词与关系副词 where, when 联系在一起。此两题错在关系词的误用上。方法二：准确判断先行词在定语从句中的成分（主、谓、宾、定、状），也能正确选择出关系代词或关系副词。例 1. Is this museum _ you visited a few days ago?A. where B. that C. on which D. the one例 2. Is this
8、the museum _ the exhibition was held.A. where B. that C. on which D. the one答案：例 1：D； 例 2：A例 1 变为肯定句： This museum is _ you visited a few days ago.例 2 变为肯定句： This is the museum _ the exhibition was held.在例 1 中，从句中所缺部分为宾语，而主句中又缺表语，所以只有 the one 可以作主句的表语，而关系代词作从句的宾语可以省略，所以选 D。而例 2 中, 主、谓、宾俱全，从句部分为句子的状语表
9、地点，既可用关系副词 where，又可用介词 in + which 引导地点状语。而此题中，介词 on 用的不对，所以选 A。关系词的选择依据在从句中所作的成分，先行词在从句中作主语、定语、宾语时，选择关系代词（who, whom, that, which, whose）；先行词在从句中作状语时，应选择关系副词（where 地点状语，when 时间状语，why 原因状语）。4 限制性和非限制性定语从句1）定语从句有限制性和非限制性两种。限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确；非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开。例如
10、：This is the house which we bought last month.这是我们上个月买的那幢房子。（限制性）The house, which we bought last month, is very nice.这幢房子很漂亮，是我们上个月买的。（非限制性）2）当先行词是专有名词或有物主代词和指示代词所修饰时，其后的定语从句通常是非限制性的。例如：Charles Smith, who was my former teacher, retired last year.查理史密斯去年退休了，他曾经是我的老师。My house, which I bought last year
11、, has got a lovely garden.我去年买的那幢房子带着个漂亮的花园。This novel, which I have read three times, is very touching.这本小说很动人，我已经读了三遍。3）非限制性定语从句还能将整个主句作为先行词，对其进行修饰，这时从句谓语动词要用第三人称单数。例如：He seems not to have grasped what I meant, which greatly upsets me.他似乎没抓住我的意思，这使我心烦。Liquid water changes to vapor, which is called
12、 evaporation.液态水变为蒸汽，这就叫做蒸发。说明：关系代词 that 和关系副词 why 不能引导非限制性定语从句。5 “介词+关系词”结构(1) 介词后面的关系词不能省略；(2) that 前不能有介词；(3) 关系副词 when，where，why 的含义相当于“介词+which”结构，因此，常常可以和“介词|+which”结构交替使用。例如：This is the house where (in which) I lived two years ago.这是我两年前住过的房子。Do you remember the day when (on which) you joined
13、 our club?还记得你加入我们俱乐部的那一天吗？6 as 和 which 引导的非限定性定语从句由 as 和 which 引导的非限定性定语从句，as 和 which 可代整个主句。as 一般放在句首，which 在句中。例如：As we know, smoking is harmful to ones health.如我们所知，吸烟有害健康。The sun heats the earth, which is very important to us.太阳使地球暖起来，这对我们很重要。注意：as 引导的定语从句可置于句首，而 which 不可；7 关系代词 that 的用法(1) 不用
14、that 的情况：引导非限定性定语从句时。例如：The tree, that is four hundred years old, is very famous here.（错）介词后不能用 that。例如：We depend on the land from which we get our food. 我们依赖土地获得食物。We depend on the land that/which we get our food from.(2) 只能用 that 作为定语从句的关系代词的情况：在不定代词，如 anything，nothing，the one，all，much，few，any，lit
15、tle 等作先行词时，只用 that，不用 which。例如：All that is needed is a supply of oil. 所需的只是供油问题。先行词有 the only，the very 修饰时，只用 that。例如：He is the only person that attended the meeting. 他是唯一参加这个会议的人。先行词被序数词或形容词最高级所修饰时，只用 that。例如：This is the most exciting film I have ever seen. 这是我看过的最令人兴奋的电影。先行词既有人，又有物时。例如：They talked
16、 of things and persons that they remembered. 他们谈论着他们记得的人和事。【真题演练】【2017天津】9. My eldest son, _ work takes him all over the world, is in New York at the moment.A. that B. whose C. his D. who【答案】B【解析】【2016江苏】23.Many young people, most _were well-educated, headed for remote regions to chase their dreams.
17、A. of which B. of them C. of whom D. of those【答案】C【解析】【2015北京】.Opposite is St.Pauls Church,_you can hear some lovely music.A. which B.that C.when D.where【答案】A【解析】试题分析：题目考查定语从句的关系词。a couple 是先行词，这对夫妻的孩子很吵，children 和 couple是所属关系，故用 whose 作定语，whose children 相当于 the children of whom，故选 A。【2014浙江】I dont become a serious climber until the fifth grade, _ I went up to rescue a kite that was stuck in the branches of a tree.A. when B. where C. which D. why【答案】A【解析】
