初中英语定语从句是怎么回事啊
⑴ 英语定语从句是怎么回事呀
定语从句（Attributive Clauses）在句中做定语，修饰一个名词或代词，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。
18.1 关系代词引导的定语从句
关系代词所代替的先行词是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人的名词或代词，在从句中所起作用如下：
Is he the man who/that wants 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）which, that
它们所代替的先行词是事物的名词或代词，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）
18.2 关系副词引导的定语从句
关系副词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。
1）when, where, why
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
that可以用于表示时间、地点、方式、理由的名词后取代when, where, why和"介词+ 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。
18.3 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；而不及物动词则要求用关系副词。例如：
This is the mountain village where I stayed last year.
I'll never forget the days when I worked together with you.
判断改错（注：先显示题，再显示答案，横线；用不同的颜色表示 出。）
（错） This is the mountain village where I visited last year.
（错） I will never forget the days when I spent in the countryside.
（对） This is the mountain village (which) I visited last year.
（对） I'll 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/关系副词。
例1. Is this museum ___ you visited a few days age?
A. where B. that C. on which D. the one
例2. Is this 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.
在句1中，所缺部分为宾语，而where, that, on which都不能起到宾语的作用，只有the one既做了主句的表语，又可做从句的宾语，可以省略关系代词，所以应选D。
而句2中, 主、谓、宾俱全，从句部分为句子的状语表地点，既可用副词where，又因 in the museum词组，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做的成分，先行词在从句中做主、定、宾语时，选择关系代词 (who, whom, that, which, whose)； 先行词在从句中做状语时，应选择关系副词 ( where 地点状语，when 时间状语，why 原因状语) 。
18.4 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：
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, has got a lovely garden. 我去年买的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 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。
18.5 介词+关系词 P>
1）介词后面的关系词不能省略。
2）that前不能有介词。
3） 某些在从句中充当时间，地点或原因状语的"介词+关系词"结构可以同关系副词when 和where 互换。
This is the house in which I lived two years ago.
This is the house where I lived two years ago.
Do you remember the day on which you joined our club?
Do you remember the day when you joined our club?
18.6 as, which 非限定性定语从句
由as, which 引导的非限定性定语从句，as和which可代整个主句，相当于and this或and that。As一般放在句首，which在句中。
As we know, smoking is harmful to one's health.
The sun heats the earth, which is very important to us.
典型例题
1）Alice received an invitation from her boss, ___came as a surprise.
A. it B. that C. which D. he
答案C. 此为非限定性从句，不能用 that修饰，而用which.，it 和he 都使后句成为句子，两个独立的句子不能单以逗号连接。况且选he句意不通。
2）The weather turned out to be very good, ___ was more than we could expect.
A. what B. which C. that D. it
答案B。which可代替句子，用于非限定性定语从句，而what不可。That 不能用于非限定性定语从句，it不为连词，使由逗号连接的两个句子并在一起在英语语法上行不通。
3）It rained hard yesterday, ____ prevented me from going to the park..
A. that B. which C. as D. it
答案B.
as 和which在引导非限制性定语从句时，这两个关系代词都指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。但不同之处主要有两点：
(1） as 引导的定语从句可置于句首，而which不可。
(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；若为行为动词，则从句中的关系代词只能用which.。
在本题中，prevent由于是行为动词，所以正确选项应为B。
As 的用法
例1. the same… as；such…as 中的as 是一种固定结构, 和……一样……。
I have got into the same trouble as he (has).
例2. as可引导非限制性从句，常带有'正如'。
As we know, smoking is harmful to one's health.
As is known, smoking is harmful to one's health.
As是关系代词。例1中的as作know的宾语；例2中，它充当从句的主语，谓语动词know要用被动式。
18.7 先行词和关系词二合一
1)Whoever spits in public will be punished here.
(Whoever 可以用 anyone who 代替)
2)The parents will use what they have to send their son to technical school.
(what 可以用all that代替)
18.8 what/whatever;that/what; who/whoever
1）what = the thing which；whatever = anything
What you want has been sent here.
Whatever you want makes no difference to me.
2) who= the person that whoever= anyone who
（错）Who breaks the law will be punished.
（错）Whoever robbed the bank is not clear.
（对）Whoever breaks the law will be punished.
（对）Who robbed the bank is not clear.
3) that 和 what
当that引导定语从句时 ，通常用作关系代词，而引导名词性从句时，是个不充当任何成分的连接词。宾语从句和表语从句中的that常可省略。What只能引导名词性从 句， 用作连接代词，作从句的具体成分，且不能省略。
I think (that) you will like the stamps.
What we need is more practice.
18.9 关系代词that 的用法
1）不用that的情况
a) 在引导非限定性定语从句时。
(错) The tree, that is four hundred years old, is very famous here.
b) 介词后不能用。
We depend on the land from which we get our food.
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
a) 在there be 句型中，只用that，不用which。
b) 在不定代词，如：anything, nothing, the one, all, much, few, any, little等作先行词时，只用that，不用which。
c) 先行词有the only, the very修饰时，只用that。
d) 先行词为序数词、数词、形容词最高级时，只用that。.
e) 先行词既有人，又有物时。
举例：
All that is needed is a supply of oil.
所需的只是供油问题。
Finally, the thief handed everything that he had stolen to the police.
那贼最终把偷的全部东西交给了警察。
⑵ 初中英语定语从句
不用啊。定语从句，你有先行词了啊，先行词在从句中充当成分
⑶ 初中英语定语从句讲解
定语从句即用句子来做定语，被修饰或被限制的词称作先行词，例如
1.I don't know the girl who is talking there.
2.I don't know the girl who you met just now.
3.Give me the book that you read just now.
4.Give me the book ,which you read just now.
5.Give me the pen that you write with.
6.Give me the pen with which you write .
仔细看句子专中的book 和pen就是先行词，他们后面属的who that which 就是引导定语从句的关系代词，当先行词是人用who,先行词是物用that,先行词后出现介词或逗号用which.
这是一种捷径，细节问题找本语法书慢慢学。
⑷ 英语的定语从句是怎么回事，好心人告诉下
定语概述
定语是用来修饰、限定、说明名词或代词的品质与特征的。 主要有形容词此外还有名词、代词、数词、介词短语、动词不定式（短语）、分词、定语从句或相当于形容词的词、短语或句子都可以作定语。 汉语中常用‘……的’表示。定语和中心语之间是修饰和被修饰、限制和被限制的关系。在汉语中，中心语与定语二者之间有的需要用结构助词“的”，有的不需要，有的可要可不要。 “的”是定语的标志。
[编辑本段]英语中的定语
The little boy needs a blue pen.(little修饰名词boy；blue修饰名词pen.）/小男孩需要一支蓝色的钢笔。
Tom is a handsome boy./Tom是个英俊的男孩。
There is a good boy./有个乖男孩。
数词作定语相当于形容词：Two boys need two pens./两个男孩需要两支钢笔。
The two boys are students./这两个男孩是学生。
There are two boys in the room./房间里有两个男孩。
代词或名词所有格作定语：
His boy needs Tom's pen./他的男孩需要Tom的钢笔。
His name is Tom./他的名字是汤姆。
There are two boys of Tom's there./那儿有Tom家的两个男孩。
介词短语作定语：
The boy in the classroom needs a pen of yours./教室里的男孩需要你的一支钢笔。
The boy in blue is Tom./穿蓝色衣服的孩子是汤姆。
There are two boys of 9,and three of 10./有两个9岁的，三个10岁的男孩。
名词作定语：
The boy needs a ball pen./男孩需要一支圆珠笔。
It is a ball pen./这是一支圆珠笔。
There is only one ball pen in the pencil box./这铅笔盒里只有一支圆珠笔。
副词作定语：
The boy there needs a pen./那儿的男孩需要一支钢笔。
The best boy here is Tom./这里最棒的男孩是Tom。
不定式作定语：
The boy to write this letter needs a pen./写这封信的男孩需要一支钢笔。
The boy to write this letter is Tom./将要写这封信的男孩是汤姆。
There is nothing to do today./今天没有事要做。
分词（短语）作定语：
The smiling boy needs a pen bought by his mother./那个微笑的男孩需要一支他妈妈买的钢笔。
The pen bought by her is made in China./她买的笔是中国产的。
There are five boys left./有五个留下的男孩。
定语从句：
The boy who is reading needs the pen which you bought yesterday./那个在阅读的男孩需要你昨天买的钢笔。
The boy you will know is Tom./你将认识的男孩叫汤姆。
There are five boys who will play the game./参加游戏的男孩有五个。
定语的位置一般有两种：用在所修饰词之前的叫前置定语，用在所修饰词之后的叫后置定语。
单词作定语时通常放在它所修饰的词之前，作前置定语。短语和从句作定语时则放在所修饰的词之后，作后置定语。
1）定语前置
在英语里,一般定语前置时的次序为:限定词，形容词、分词、动名词和名词性定语。但当几个形容词同时出现在名词短语之前,我们要注意其次序。其形容词遵循的词序为：限观形龄色国材，指：限定词（一般指数量）；外观（美丽等）；形状（大小，高矮，肥瘦）；年龄；颜色；国籍；材料；用途。如：
1限定词 2 外观 3形状 4年龄 5颜色 6国籍 7材料 8用途
A famous American university.
An interesting little red French oil painting.
A new plastic bucket.
A purple velvet curtains
An elegant German clock
另外,有些形容词也有特殊的次序:
(1) 描述身体特征的形容词先于表示情感和性格特征的形容词
例如:a small lovely girl , a long patient queue , a pale anxious patient ;
(2) 表示颜色的形容词放在表示情感和性格特征的形容词之后
例如:a kindly black teacher ,an inquisitive brown dog ;
(3) little ,old 和young 有时可以作为名词短语不可分割的一部分,所以可以直接放在名词之前,
例如:a lovely little girl
(4) 表示性格特征的形容词可以放在old young 之前,也可放在old young 之后,例如:
a young ambitious man (强调年龄) ,an ambitious young man(强调雄心勃勃) 。
当然,三个以上形容词连用作定语,就显得累赘,因此上面所说的情况一般较少出现.
2）定语后置
(1）短语作定语一般后置
It was a conference fruitful of results. 那是一个硕果累累的会议。
He gave me a basket full of eggs. 他给我一个装满鸡蛋的篮子。
English is a language easy to learn but difficult to master. 英语是一门容易学但是难精通的语言。
The boys hardest to teach are all in his class.最难教的男生都在他的班里了。
（2）修饰some，any，no，every等词构成的不定代词的定语都后置
Let’s go somewhere quiet. 咱们去找个安静一点的地方吧。
There is nothing important in today's newspaper. 今天报纸上没有什么重要的东西。
Do you have anything more to say? 你还有什么话要说吗?
（3）副词作定语
The people here are very friendly. 这里的人很友好。
They lived in the room above.他们住在楼上的房间。
（4）动词、名词转化而来的以-able,-ible 结尾的形容词作定语
He is a person dependable. 他是一个可以依靠的人
This is the only transportation means available. 这是唯一可行的交通工具。
（5）起强调用的单个分词
Everybody involved should stay here.
The college mentioned.
（6）特殊词
Could you tell me something imporpant.
3) 定语从句
英语里有大量的定语从句,而汉语里却没有定语从句的说法。英语中定语从句中甚至还可能包含定语从句,即多重定语从句。如： A healthy diet includes enough but not too many kinds of foods that provide the body with the nutrients that it needs to function properly. (健康的饮食包括的食物应该充足但又不过多。这些食物提供身体正常活动所必需的营养)
(1）英语的复合句中,分句以其主句为基干,通过连接手段,一层一层地展开,就好像一棵树的树干上长出大枝子,大枝子上再长出小枝子。汉语的分句则更多按照时间发生的顺序出现,依次展开。
如： “伟大领袖和导师毛主席领导中国共产党进行了艰苦卓绝的斗争,建立了新中国,人民得到了解放,科学得到了解放。”这句话,译成英语便成了With the founding of new China (which was) born of arous struggles (which were) waged by the Chinese Communist Party (which was) under the leadership of our great leader and teacher Chairman Mao , our people , and science as well , won emancipation.（王良兰，2003）
(2）英语中的非限制性定语从句所表达的信息,在汉语里一般由另一个小句来表达。用非限制性定语从句时，前应加逗号，并且非限制性定语从句引导词只能用which，不能用that。
例如:She asked for his help which he gladly gave. 她要求他帮忙,他愉快地帮助了她。
再如: It was a century ring which the country suffered continuously from wars.
一个世纪过去了,在这期间这个国家不断遭受战乱之苦。
⑸ 初中英语：定语从句的用法
1.what不能引导定语从句.
2.关系词的分析须考虑它在定语从句中的成分。
一.指人的关系代词有who、whose、whom、that. 试分析：
The old man who/whom /that we visited yesterday is a famous artist.
Miss Wang is taking care of the child whose parents have gone to Beijing .
The man with whom my father shook hands just now is our headmaster. （=The man who/whom that my father shook hands with just now is our headmaster.）注：
A．指人时有时只用who不宜用that。
1．先行词为one、ones或anyone
（1）The comrade I want to learn from is the one who studies hard and works hard.
（2）Anyone who breaks the law should be punished.
2．先行词为these时
These who are going to Beijing are the best students of our school.
3．在there be 开头的句子中
There is a student who wants to see you.
4．一个句子中带有两个定语从句，其中一个定语从句的关系代词是that，另一个宜用who，以免重复。
The student that won the first prize is the monitor who works hards.
5．在非限制性定语从句中
A。I met a friend of mine in the street, who had just come from Japan.
B．主句以who开头的句子中,只用that,不用who。
二．指物的关系代词有which、whose(=of which)、that. 试分析：
1. I like the books which / that were written by Lu Xun.
2. The desks (which/that) we made last year were very good.
3. This is the house in which we lived last year. (= This is the house which /that we lived in last year.)
4. I live in the room whose windows face south. (= I live in the room ,the windows of which face south.)
注：
A. 介词如果位于作为其宾语的关系代词之前时，只能用whom、 which不能用who或that.
(1). The girl about whom they were talking is our monitor.
(2). The book in which there are many interesting things was written by Li Ming.
B. 部分短语动词中的介词不可与动词拆开，在定语从句中其介词不可前置，只能放在其动词之后。
Is this the book which she is looking for?
The old man who/whom they are waiting for is Professor Li.
The child who/whom she is looking after is Wang Ping’s son.
C．指物时，下列情况下只能用that ，不宜用which。
（1）先行词为不定代词，如All、much、anything、everything、nothing、something、none、the one等。
We are willing to do anything that is good to the people.
I have told them all (that) I know.
All that can be done has been done.
（2）先行词是序数词或被序数词、修饰时。
The first book that I read last night was an English novel.
（3）先行词是形容词最高级或被最高级修饰时。
This is one of the most interesting films that I have ever seen.
This is the best that can be done now.
（4）如果有两个或两个以上分别表示人和物的先行词时(先行词既有人又有物)，定语从句的关系代词用which和who都不合适，只能用that。
We know nothing about the doctors and the hospitals that you are talking about.
There are sheep and men that can be seen on the hill.
（5）如果先行词被the only、the very、the last、the same、any、 few 、little、no、 all 、one of、 just修饰时。
This is the only book that can be lent to you.
（6）当主句是以which开头的特殊问句时，关系代词只用that。
Which is the dictionary that he used yesterday ?
D．只物时，下列情况下只能用which，不宜用that。
（1）关系代词放在介词之后
This is the factory in which we once worked.
（2）非限制性定语从句中
This is the book, which is written by Lu Xun.
（3）that，Those作主语时
Those which are on the desk are English books.
E．先行词前有such、the same、 as时, 关系代词用as，不用that, 但the same…as…表示同样的, the same…that…表示同一的
He knows as many people as are present at the meeting.
Such people as you refer to are rare nowadays.
三．比较When/which、where /which、why.
which I still never forget.
This is the day when I joined the party.
which he spent reading the books.
where I found the book.
which makes machines.
This is the place which we once visited.
which I will never forget.
which I am looking for.
限制性定语从句与非限制性定语从句的区别：
限制性定语从句
非限制性定语从句
All the students who study hard have passed.学习努力的学生都考试及格了。(只有努力的及格了，不努力的没及格。) All the students ,who study hard have passed.所有的学生都及格了，他们学习努力。（没有人不及格，这些学生都很努力。）
从句是先行词不可缺少的定语（如去掉，主句意思就不完整或不正确。）从句是对先行词的附加说明（如去掉，主句意思仍清楚，不受影响。）与主句关系密切，不用逗号与主句关系不十分密切，用逗号与主句隔开译为汉语时，从句译在先行词前，与先行词用“的”连接译为汉语时，从句放在主句后面关系代词that可以代替who、whom(指人)、which(指物) 关系代词不用that,只用who、whom(指人)、which(指物) 关系代词代替宾语时可以省略关系代词不能省略关系代词as和which
先研究下面两个例句：
○1.This elephant is like a snake, as /which everybody can see. =As everybody can see, this elephant is like a snake. 任何人都看得出来，这头象像条蛇。
○2.Tom didn’t pass the physics exam, which made his parents very angry. Tom物理考试不及格，这使得他父亲很生气。
这两个例句中，as和which所代表的都是整个主句所表示的内容。但有两点不同之处：
1．在形式上as引导的非限制性定语从句可位于主句的后面，也可位于主句的前面；而which引导的非限制性定语从句只能位于主句的后面，不能位于主句的前面。
2．在意义上，as引导的定语从句和主句的关系一般为一致关系，常译为“正如……”，“就像……”，而which引导的定语从句和主句的关系是因果关系，或which引导的定语从句是对主句的评论。因此，在意思通顺的情况下，which可代替as，而as许多时候不能代替which，如句○2。再如：
1．He was late again, as / which we had expected. =As we had expected, he was late again. 正如我们所料，他又迟到了。/他又迟到了这是我们早就料到的。
2． The street hasn’t been cleared for weeks, which makes it very dirty. 街道好多星期没有打扫了，因此整条街很脏。（不用as）
3．The young man cheated his friend of much money, which was disgraceful. 那年轻人诈骗了他朋友许多钱财，这是不光彩的。（不用as）
4．He takes exercise everyday, which has done a lot of good to his health. 他每天运动，这对他的身体很有好处。（不用as）
5．As has already been pointed out, English is rather difficult for a foreigner. 正如已经指出的那样，英语对于初学者说，是相当难学的。在such…as…、the same…as…、 as…、 as many…/much as…等结构中,as不能用which代替。如：
1.Such books as this are too difficult for beginners. 这样的书对于初学的人来说是太难了。
=Books such as this are …
=Books like this are …
2.I live in the same building as he (does). 我和他住再同一座大楼里。
3.He knows as many people as are present at the meeting. 他认识所有到会的人。
4.That day we all got up early as usual. 那天我们和平时一样，都起得很早。
“One of the +复数名词”后面定语从句中谓语单复数情况
这一结构后面的定语从句的谓语动词通常用复数形式，跟定语从句所靠近的那个复数名词在数上保持一致。如：
1． That is one of the books that are required for study at school.
2． This is one of the most wonderful novels that have been published since 1990.
3． She is one of the few persons who know Spanish .
4． This is one of the most famous plays that were written in the thirties,
如果one of +复数名词这一结构前面带有the only、the very之类的限定语，后面定语从句的谓语动词则要用单数形式，这是因为定语从句在意义上修饰的是而不是那个复数名词。如：
1.He is the only one of the teachers who knows French in our school.( 修饰the only one)
He is one of the teachers who know French in our school.( 修饰the teachers)
2.This is the only one of the rooms that is free now. (修饰the only one)
This is one of the rooms that are free now. (修饰rooms)
as与which引导的定语从句
两者均可引导非限制性定语从句，有时可以互换，但下列情况多用as。
1. 关系代词引导的定语从句居句首时。 As we all know, the earth is round.
2. 当与such或the same连用时，一般用as。 Such books as you tell me are interesting. I have the same plan as you.
3. 当从句和主句语义一致时，用as，反之则用which。 She has married again, as was expected. She has married again, which was unexpected.
4. as在从句中作主语时，后面常接行为动词的被动语态，如be known，be said，be reported等，如从句中行为动词是主动语态，一般要用which作主语。
She has been late again, as was expected.
Tom has made great progress, which made us happy.
⑹ 初中英语定语从句问题
这句话有两种说法
一是 All that 这是定语从句 先行词是all 如果只有that 那就没有先行词了 当然也回不对答了
二是 What 这句话就是宾语从句 和in是介宾结构 What是宾语从句里做宾语
若有疑问 欢迎来问我 望采纳
⑺ 初中英语定语从句的用法
1.what不能引导定语从句.
2.关系词的分析须考虑它在定语从句中的成分。
一.指人的关系代词有who、whose、whom、that. 试分析：
The old man who/whom /that we visited yesterday is a famous artist.
Miss Wang is taking care of the child whose parents have gone to Beijing .
The man with whom my father shook hands just now is our headmaster. （=The man who/whom that my father shook hands with just now is our headmaster.）注：
A．指人时有时只用who不宜用that。
1．先行词为one、ones或anyone
（1）The comrade I want to learn from is the one who studies hard and works hard.
（2）Anyone who breaks the law should be punished.
2．先行词为these时
These who are going to Beijing are the best students of our school.
3．在there be 开头的句子中
There is a student who wants to see you.
4．一个句子中带有两个定语从句，其中一个定语从句的关系代词是that，另一个宜用who，以免重复。
The student that won the first prize is the monitor who works hards.
5．在非限制性定语从句中
A。I met a friend of mine in the street, who had just come from Japan.
B．主句以who开头的句子中,只用that,不用who。
二．指物的关系代词有which、whose(=of which)、that. 试分析：
1. I like the books which / that were written by Lu Xun.
2. The desks (which/that) we made last year were very good.
3. This is the house in which we lived last year. (= This is the house which /that we lived in last year.)
4. I live in the room whose windows face south. (= I live in the room ,the windows of which face south.)
注：
A. 介词如果位于作为其宾语的关系代词之前时，只能用whom、 which不能用who或that.
(1). The girl about whom they were talking is our monitor.
(2). The book in which there are many interesting things was written by Li Ming.
B. 部分短语动词中的介词不可与动词拆开，在定语从句中其介词不可前置，只能放在其动词之后。
Is this the book which she is looking for?
The old man who/whom they are waiting for is Professor Li.
The child who/whom she is looking after is Wang Ping’s son.
C．指物时，下列情况下只能用that ，不宜用which。
（1）先行词为不定代词，如All、much、anything、everything、nothing、something、none、the one等。
We are willing to do anything that is good to the people.
I have told them all (that) I know.
All that can be done has been done.
（2）先行词是序数词或被序数词、修饰时。
The first book that I read last night was an English novel.
（3）先行词是形容词最高级或被最高级修饰时。
This is one of the most interesting films that I have ever seen.
This is the best that can be done now.
（4）如果有两个或两个以上分别表示人和物的先行词时(先行词既有人又有物)，定语从句的关系代词用which和who都不合适，只能用that。
We know nothing about the doctors and the hospitals that you are talking about.
There are sheep and men that can be seen on the hill.
（5）如果先行词被the only、the very、the last、the same、any、 few 、little、no、 all 、one of、 just修饰时。
This is the only book that can be lent to you.
（6）当主句是以which开头的特殊问句时，关系代词只用that。
Which is the dictionary that he used yesterday ?
D．只物时，下列情况下只能用which，不宜用that。
（1）关系代词放在介词之后
This is the factory in which we once worked.
（2）非限制性定语从句中
This is the book, which is written by Lu Xun.
（3）that，Those作主语时
Those which are on the desk are English books.
E．先行词前有such、the same、 as时, 关系代词用as，不用that, 但the same…as…表示同样的, the same…that…表示同一的
He knows as many people as are present at the meeting.
Such people as you refer to are rare nowadays.
三．比较When/which、where /which、why.
which I still never forget.
This is the day when I joined the party.
which he spent reading the books.
where I found the book.
which makes machines.
This is the place which we once visited.
which I will never forget.
which I am looking for.
限制性定语从句与非限制性定语从句的区别：
限制性定语从句
非限制性定语从句
All the students who study hard have passed.学习努力的学生都考试及格了。(只有努力的及格了，不努力的没及格。) All the students ,who study hard have passed.所有的学生都及格了，他们学习努力。（没有人不及格，这些学生都很努力。）
从句是先行词不可缺少的定语（如去掉，主句意思就不完整或不正确。）从句是对先行词的附加说明（如去掉，主句意思仍清楚，不受影响。）与主句关系密切，不用逗号与主句关系不十分密切，用逗号与主句隔开译为汉语时，从句译在先行词前，与先行词用“的”连接译为汉语时，从句放在主句后面关系代词that可以代替who、whom(指人)、which(指物) 关系代词不用that,只用who、whom(指人)、which(指物) 关系代词代替宾语时可以省略关系代词不能省略关系代词as和which
先研究下面两个例句：
○1.This elephant is like a snake, as /which everybody can see. =As everybody can see, this elephant is like a snake. 任何人都看得出来，这头象像条蛇。
○2.Tom didn’t pass the physics exam, which made his parents very angry. Tom物理考试不及格，这使得他父亲很生气。
这两个例句中，as和which所代表的都是整个主句所表示的内容。但有两点不同之处：
1．在形式上as引导的非限制性定语从句可位于主句的后面，也可位于主句的前面；而which引导的非限制性定语从句只能位于主句的后面，不能位于主句的前面。
2．在意义上，as引导的定语从句和主句的关系一般为一致关系，常译为“正如……”，“就像……”，而which引导的定语从句和主句的关系是因果关系，或which引导的定语从句是对主句的评论。因此，在意思通顺的情况下，which可代替as，而as许多时候不能代替which，如句○2。再如：
1．He was late again, as / which we had expected. =As we had expected, he was late again. 正如我们所料，他又迟到了。/他又迟到了这是我们早就料到的。
2． The street hasn’t been cleared for weeks, which makes it very dirty. 街道好多星期没有打扫了，因此整条街很脏。（不用as）
3．The young man cheated his friend of much money, which was disgraceful. 那年轻人诈骗了他朋友许多钱财，这是不光彩的。（不用as）
4．He takes exercise everyday, which has done a lot of good to his health. 他每天运动，这对他的身体很有好处。（不用as）
5．As has already been pointed out, English is rather difficult for a foreigner. 正如已经指出的那样，英语对于初学者说，是相当难学的。在such…as…、the same…as…、 as…、 as many…/much as…等结构中,as不能用which代替。如：
1.Such books as this are too difficult for beginners. 这样的书对于初学的人来说是太难了。
=Books such as this are …
=Books like this are …
2.I live in the same building as he (does). 我和他住再同一座大楼里。
3.He knows as many people as are present at the meeting. 他认识所有到会的人。
4.That day we all got up early as usual. 那天我们和平时一样，都起得很早。
“One of the +复数名词”后面定语从句中谓语单复数情况
这一结构后面的定语从句的谓语动词通常用复数形式，跟定语从句所靠近的那个复数名词在数上保持一致。如：
1． That is one of the books that are required for study at school.
2． This is one of the most wonderful novels that have been published since 1990.
3． She is one of the few persons who know Spanish .
4． This is one of the most famous plays that were written in the thirties,
如果one of +复数名词这一结构前面带有the only、the very之类的限定语，后面定语从句的谓语动词则要用单数形式，这是因为定语从句在意义上修饰的是而不是那个复数名词。如：
1.He is the only one of the teachers who knows French in our school.( 修饰the only one)
He is one of the teachers who know French in our school.( 修饰the teachers)
2.This is the only one of the rooms that is free now. (修饰the only one)
This is one of the rooms that are free now. (修饰rooms)
as与which引导的定语从句
两者均可引导非限制性定语从句，有时可以互换，但下列情况多用as。
1. 关系代词引导的定语从句居句首时。 As we all know, the earth is round.
2. 当与such或the same连用时，一般用as。 Such books as you tell me are interesting. I have the same plan as you.
3. 当从句和主句语义一致时，用as，反之则用which。 She has married again, as was expected. She has married again, which was unexpected.
4. as在从句中作主语时，后面常接行为动词的被动语态，如be known，be said，be reported等，如从句中行为动词是主动语态，一般要用which作主语。
She has been late again, as was expected.
Tom has made great progress, which made us happy.
⑻ 英语的定语从句是怎么回事的呀!!!
定语从句（Attributive Clauses）在句中做定语，修饰一个名词或代词，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。 18.1 关系代词引导的定语从句
关系代词所代替的先行词是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人的名词或代词，在从句中所起作用如下：
Is he the man who/that wants 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）which, that 它们所代替的先行词是事物的名词或代词，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 18.2 关系副词引导的定语从句
关系副词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。
1）when, where, why
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
that可以用于表示时间、地点、方式、理由的名词后取代when, where, why和"介词+ 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。
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；而不及物动词则要求用关系副词。例如：
This is the mountain village where I stayed last year.
I"ll never forget the days when I worked together with you.
判断改错（注：先显示题，再显示答案，横线；用不同的颜色表示出。）
（错） This is the mountain village where I visited last year.
（错） I will never forget the days when I spent in the countryside.
（对） This is the mountain village (which) I visited last year.
（对） I"ll 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。