限制性定语从句与非限制性定语从句的区别
限制性定语从句提供有关主语或宾语的重要信息，起限定作用，与被修饰部分的关系紧密，如果省略该从句会使主句语义表达不完整。例如：
This is the very person that is wanted by the police. He is the man who /that lives next door.
It was a meeting whose importance I did not realize at the time.
非限制性定语从句只是用来对被修饰部分作补充性的说明，与先行词关系比较松散，先行词与从句间可以用逗号隔开，从句可略去：
He will not be able to spend the holiday with his family, which is a big annoyance to him.
The minister, who is to visit our university, is said to be a Qinghua University graduate.
The book , which your sister bought you in Xinhua Bookstore , is very useful in improving your spoken English.
The businessman, whose suitcase has been found by a stranger , has left for Beijing.
如果定语从句的先行词是专有名词或是带有形容词性物主代词(my, his, etc) 或形容词性指示代词(this, that, etc) 作限定词的名词词组，其后的定语从句通常为非限制性的。例如：
The Thames , which is now clean enough to swim in , was polluted for over a hundred years.
My mother , who has been on a visit to Australia, will fly back tomorrow.
All of these books, which have been donated by visiting professors , are to be used by the children in Hope School.
限制性定语从句的先行词只能是名词，代词或名词性词组，而非限制性定语从句的先行词除了是名词及名词性
词组外，还可能是句子的一部分或是整个句子。例如：
They say he plays truant, which he doesn’t. [which指代plays truant]
The meeting was put off till next month, as we hoped.
[as指前面的句子]
下面的表格归纳了前面已提到的两者不同之处： 表一：限制性定语从句与非限制性定语从句的区别
3.2 定语从句中的关系代词
3.2.1 关系代词that, which, who在定语从句中做主语
在限制性定语从句中，who 或that 用于指人，that 或
which 用于指物，它们在定语从句中代替名词性主语或代词性主语，不能省略。例如：
He is the man who/that lives here. [不能说：×He is the man who he lives here.]
The bag which ／that has been put there for a long time belongs to Wang Hong．
3.2.2 who(m), which, that在定语从句中作宾语
表示人的时候用who(m)或that, 它们在从句中代替名词性宾语或宾格代词，作定语从句宾语的whom/that通常可以省略，在口语中常用who 代替 whom 。例如：
He’s the man whom / that I met.
There are some people here who I want you to meet. 表示动物和东西的时候应用which/that:
The pieces of music (that ) he has composed are sung by many pop singers.
Taxes consist of money (that ) people pay to support their government.
They’re the postcards which I sent from America.
3.2.3 who(m), which或 that 作介词的宾语，关系代词可省略。
定语从句的介词的位置非常重要，我们可以说： He is the person to whom I wrote. [非常正式用法] (但不可以说：×to who).
或：He is the person who (m ) I wrote to . /He is the person (whom ) I wrote to.
This is the pan in which I boiled the milk. [非常正式用法]
或：This is the pan which I boiled the milk in. / This is the pan (that/which) I boiled the milk in.
3.2.4 whose + 名词
关系代词whose 是既可用于限制性定语从句，也可用
于非限制性定语从句，在从句中作定语，一般用来指人，代替所有格形容词（my, his, your, her, its等），在从句中当定语，没有阴性、阳性或单数、复数的变化；有时也可指物，指物时可以用of which 代替。例如：
The professor whose daughter teaches you English is Dr. Williams.
The bicycle whose brake was damaged has now been
repaired. =The bicycle, the brake of which was damaged , has now been repaired.
Edison is a great inventor whose fame is world-wide.
3.2.5 that 的用法
1、that 只用于限制性定语从句，既可指人，又可指物，在句中用做主语或宾语。（见3.2.1、3.2.2）
2、当先行词是all ，much ，little, the one, anything, something, nothing, everything, none等不定代词时，关系代词只用that 。例如：
There is little that can be done about it.
That's all that I knew about it.
Is there anything that I can do for you?
Have you done everything that is assigned to you?
3、先行词被形容词最高级以及first, last, any, only, few, much, no, some, very等词修饰时，关系代词只用that 。例如：
It is the most interesting film that I’ve ever read.
The best thing that he could do at present is to leave. This is the first time that he has been there.
She is the only one that has finished her task on time. At the very beginning, we have just too much work that needs to be done.
4、在there be 句型中，只用that, 不用which 。例如：
There are some people that I’d like to introduce to you .
There is a very interesting story that every child
would like to listen to.
5、先行词既有人，又有物时，用that 。例如：
A victim is a person, animal or thing that suffers pain, death, harm, etc.
The man and his dog that were napping outside the room were photographed by the journalist.
6、在“It is + 名词 + 定语从句1 + 定语从句2”的强调结构中，从句2要用 that 。例如：
It is always the mouth which talks too much that incurs troubles. （言多必失。）
It is only a man who is quite experienced that can fulfill this task.
3.2.6 which 的用法
1、which 一般只用于指物(a)，有时也用来指性别不明的婴儿(b)。例如：
a: The tiles which fell off the roof caused serious damage.
b: The baby which the nurse has just brought in is John’s child.
2、如果指物的关系代词紧跟在介词后面，只能用which ，不能用that 。例如：
This is the house in which she spent her childhood. The agency from which we bought our tickets is bankrupt.
3、引导非限制性定语从句时，用来指物替代名词词组。例如：
This book , which has only been reviewed , was published a year ago.
4、替代整个句子或句子的一部分：
The meeting has been put off till next Friday, is good news to them. (指代整个主句)
She said that her son would become a scientist, we thought possible. (指代that 分句)
She is very attentive in class, 指代
整个短语)
3.2.7 as 的用法
1、as 引导限制性定语从句时，常与such 或the same 连用，构成the same…as; such…as结构，as 用于代替指人或物的先行词。例如：
I have never eaten such tasty foods as she cooked me .
Such books as there were on the shelf interested us. I have got into the same trouble as he (has).
试比较 the same…as和 the same…that：
This is the same book as I read last week（. 这和我上周读的那本书是一样的。）
This is the same book that I read last year. （这就是我上周读的那本书。）
如果先行词表示抽象概念，则没有这种区别，例如：
She told me the same story as/that she had told you. I had the same difficulty that/as you had last year.
在as ／so…as结构中，后面的as 也是关系代词，例如： We took as many men as could be permitted to attend the meeting.
You can stay here as long as you like.
Things do not go on as smoothly as we hoped.
2、引导非限制性定语从句
关系代词as 引导非限制性定语从句时，用于代替整个主句，意思是“正如”， 相当于 and this 或 and that。as 从句位置较之which 引导的非限制性定语从句更加灵活，因而as 从句既可以指前面提到的内容，也可以指后面将要提到的内容，which 一般在主句后。例如：
As is mentioned above , this method aims at improving the students’ ability in a more effective way.
The test is cancelled, as you have hoped.
The test, as you have hoped, is cancelled.
A semiconductor material, as the name indicates, has
poorer conductivity than a conductor.
▲注：as 代表前面的整个主句并在从句中做主语时表达的意思应与主句一致，而且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. 例如：
He failed to pass the exam again, as is predicted.
He failed to pass the exam again, which annoyed his mother greatly.
记住以下的as 结构：
as is known to all (众所周知) ，as is often the case (情况常常如此) ，as the name Indicates／suggests (顾名思义) ，as may be imagined (可以想象得出) ，as often happens (这种情况常常发生) ，as has been said before (如前所述) ，as has been pointed out (正如已经指出的) ，as will be shown in ( 将在…中指出) ，as is hoped ( 正如所希望的)
3.2.8 but 的用法
but 用作关系代词相当于who…not，which…not，that…not。but 既可指人，也可指物，常在定语从句中充当主语或宾语。but 本身含“否定”的意思，它前面的主句通常有“否定”的词, 如：(no，not ， little ，few ，hardly 等). but引导的肯定定语从句和否定的主句连用，达到强烈肯定的修饰效果。例如：
There is no mother loves her own children. (=There is no mother does not love her own children.)[主语]
There is scarcely a good movie (=that he has not seen). [宾语]
There is never a friend of. [介词宾语] Who is there commits errors？[but间或也可用在疑问句后]
There is no man but errs . =There is no man who does not err. [主语]
What he saw in those places but was not miserable （but=which was not）(他所到之处，看到的均是凄惨不已的景象。)[主语]
There are very few but admire his talents.（很少有人不赞赏他的才干的。But=who don’t）[主语]
but 结构有时可省略。例如：
(There is)No rule but has exceptions.
(There are）Few books but have a misprint or two.
3.2.9 than 的用法
关系代词than 一般用于含有比较级的句子中，兼有连词和代词的性质。例如：
You spent more money than was intended to be spent. She has done much more work than was required of her .
The question is more complicated than appears on the surface.
3.3 介词 + 关系代词
“介词 + 关系代词”引导的定语从句既可以是限制性定语从句，又可以是非限制性定语从句，“介词+关系代词”在从句中做主语、宾语、状语、定语等，介词的选择则要根据它与其先行词的关系或前后名词、动词等的搭配关系来决定，同时还应该考虑句子在上下文中要表达的意思。
3.3.1“介词 + which ／whom ／whose”
这时应注意介词与句中短语的搭配。例如：
The problem with which I have trouble has now been solved.
Oil , of which there are several different types, is used for many purposes by countries all over the world.
The man, because of whose help the murderer was caught by the police , is coming to our school
tomorrow.
介词放在关系代词之前的形式的定语从句较之将介词至于从句之末的定语从句正式，因此多用于书面语当中，但在口语中有时也会出现；或者将介词后置，或在介词后置后用 that （人、物）／who （人）代替 which ／whom ，并且that 可省略。例如；
Can you lend me a pen or pencil with which I can write ?
Can you lend me a pen or pencil that / which I can write with ?
Can you lend me a pen or pencil (that ) I can write with ?
Who is the man to whom you were talking?
Who is the man whom /that /who you were talking to ?
Who is the man (that ) you were talking to ?
如果介词过长，则不适于后置，例如：
Sound is a tool , by means of which people communicate with each other.
We may be caught by a fire , in case of which we must find ways to escape.
3.3.2“名词 + 介词 + which／whom”引导的定语从句
He referred to a person the name of whom slipped by memory at that moment.
We had a discussion the purpose of which was to find a solution to this problem.
在非限定性定语从句中，of which ／whom 可用来修饰不定代词 all, each, one, many, much, more, most, any, some, a few, a little, none, both, several, the latter, the former等。练习时，应该判断填空的部分为主句的定语从句还是与主句并列的成分。例如：
We have interviewed more than 50 students , only a few of whom gave satisfactory answers to our
questions. [定语从句]
We have interviewed more than 50 students, but only a few of them gave satisfactory answers to our questions. [并列]
Many people came to her graduation party, most of whom were her former classmates. [定语从句]
Many people came to her graduation party, and most of them were her former classmates. [并列]
There are 32 students in our class, up to 20 of whom are from the south. [定语从句]
3.3.4 “介词 + which + 名词”引导的定语从句
which 是一个代表所有关系的关系代词，可用来代表一个名词／代词或句子的一部分，但更多地是来代表整个句子。其中的名词通常是一个抽象名词，如case, fact, state, time, point等。例如：
Water boils at l00℃, at which temperature it changes into gas.
He was about to leave, at which moment I came back home .
Wei Hua spent four years in the United States, during which period she studied law.
Reader's Digest , to which we have just subscribed , has an enormous circulation.
3.4定语从句中的关系副词
关系副词引导的定语从句（限制性／非限制性）在从句中作状语，意思相当于“介词+which”，常见的引导定语从句的关系副词有：where, when和why 等，不常见的如表示时间的关系副词：since, after和before 。
3.4.1 关系副词 where （= at, in which）引导表示地点的定语从句
This is the place where he’d most like to live the rest of his life.
London is the city where she was born.
That is the place where they met for the first time.
在表示“情况、方面、状况”等有地点含义的抽象名词如case, game, spot, point, conditions, situation, circumstances 等作为先行词的定语从句时，也用 where 引导, 其意义相当于 under which。例如：
It’s a kind of game where you can train your eyesight Everyone may face the situation where you have to make a decision yourself.
I’ll show him the point where he failed.
Under the circumstances where food shortage is the most serious problem , we must try our best to seek international aid.
3.4.2 关系副词 when （= at, on, during, in which）引导表示时间的定语从句
I’ll never forget the day when (=on which) I first came to this university.
This is the season when (=in which) most fishers will be very busy.
That is the time when many Americans were out of work .
Most people like to go there in May , when the flowers are in full bloom.
3.4.3 关系副词 why （= for which）引导表示原因的定语从句
Do you know the reason why he left the party early that night?
The reason why she missed the train is that she was held up by an accident.
3.4.4 其他关系副词引导的定语从句
I miss you every day since I came here.
On the day before she got married, her mother handed her the family heirloom.
The month after she took the entrance examination was spent in relaxing herself
3.5 关系代词和关系副词的省略
3.5.1关系代词的省略
1、关系代词which, whom, who, that在定语从句中作直接宾语时可以省略
Here is the man (who/that/whom) you’ve been looking for .
The woman (whom/who/that) I was talking to is our English teacher.
Is there any question (that ) you want to ask me?
2、当 that 在从句中作补语时可以省略
George is not the man (that ) he used to be.
He is all (that ) a teacher should be.
3、在there be结构中出现定语从句，或在定语从句中出现there be结构时，用做主语的关系代词that 可省略
There is a man downstairs (who ) wants to see you.
This is the best dictionary (that ) there is in the library. That’s all (that ) there is to it. (如此而已。)
Have you noticed anything (that ) there is happening in the company?
3.5.2 关系副词的省略
1、当先行词是reason ，而且在定语从句中做原因状语时，关系代词可用why 或that ，可以省略
The reason (why/that) he failed was his laziness.
That is the reason (why ) I did it.
2、当先行词是way ，且在定语从句中作方式状语时，关
系代词可用 in which或that ，可以省略
The way (in which/that) these comrades look at problems is wrong.
That was the way (in which/that) she worked the problem out.
注意：当关系代词在定语从句中做主语时，不省略。例如：
I don’t know the way that/which leads to the top of the mountains .
3、当先行词表示时间时，关系代词可用when 或有时用that ，有时也可以省略
The second time (that ) I saw him was in 1980.
I don’t know the exact time (when/that) the sports meet will take place.
His grandpa still remembers the day (that/when) the city was liberated.
4、当先行词表示地点时，关系代词可用where 或有时用that ，有时也可以省略
This is the village (where/that) the great man spent his childhood.
Do you know the site (where/that) this ancient tomb was discovered.
I know the place (that/where) she lives.
3.6 what 关系代词
3.6.1 “what is（was ）+ 形容词比较级”结构
what 泛指上文或下文，意思是“更……，尤其……”。该结构常为插入语：
She is very intelligent, and what’s more , very hard-working.
Great men are often unknown, or what is worse , misknown.
She decided, what was the only choice , that she
would keep it a secret.
3.6.2 what = 先行词 + 关系词
what 相当于 the thing（s ）which 或 the person（s ）that, 既可以指人，也可指物，意思相当于“……的（人或物）”，此种情况的what 本身已包含先行词，因而其前不能再有先行词。what 在其从句中可以做主语、宾语和表语。例如：
This is what you call fashion?
That is exactly what you are told to do?
Never pretend to be what you are not.
She is what we call an optimist.
3.6.3 “what + 名词” = “all the + 名词 + that”
what 在从句中作定语。例如：
On her death, the old woman gave what property she had to the young man who stayed with her during the last years of her life. (= all the property that)
We will give you what help we can . (= all the help that)
He shared what little water he had with his companions. (= all the little water that)
What poems we have learned at present are about love. (=all the poems that)
3.7 先行词与其定语从句的分割
有时先行词与其定语从句会被其他的一些语法成分割裂开来，如：状语、定语或谓语等。例如：
We have made a number of creative advances in theoretical research of applied science which are up to advanced world levels.
Do you remember one afternoon ten years ago when l came to your house and borrowed a diamond
necklace ?
During the construction, problems often arise which require design changes.
3.8 定语从句与同位语从句的区别（详见2.5.2）
3.9 关系代词与关系副词的判断
3.9. 1谓语动词是否及物
用关系代词还是关系副词完全取决于从句中的谓语动词。从句中如果及物动词后面接宾语，就必须要用关系代词；而不及物动词则要求用关系副词。例如：
The days when we stayed together are unforgettable. （stay 不及物）
I’ll never forget the days which I spent with you in Tokyo .（spend 及物，有宾语）
This is the reason why he did not come that morning. (come不及物动词)
This is the reason which/ that he found to excuse for himself. (find及物动词 )
3.9.2先行词在定语从句中的成分（主、谓、宾、定、状）
先行词表示时间、地点或原因时，就选用关系副词，用when ，where 或why ，在从句中应该是做状语，否则的话则应该用which ／that 等，that 有时可以代替when ，where 或why ，但when ，where 或why 中不能代替that 。例如：
1. Is this museum you visited a few days ago?
A. where B. that C. on which
D . the one
the exhibition was held.
A . where B. that C. on which
D. the one
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 ；而在句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 。
当从句的逻辑主语是some, any, no, somebody, anybody, nobody, something, anything, everything或nothing 时，常用there is来引导。例如：
I don’t want to concentrate on anything there is worrying me.
引导条件从句的连词
引导条件从句的连词比较多，我们可以把它们分为以下几个大类：
1、表示“只要、只有”：as, as (so) far as, as (so) long as, only if, only that, but that：
As (So) long as we don’t lose heart, we’ll find a way to overcome the difficulty.
There’s war in so far as there’s the earth beneath our feet.
But that he is ill, he would stay at home.
2、表示“如果”：if, in case (that), provided/providing (that), suppose/supposing（that ）[仅用在问句中], in the event (that):
If you are not too tired, let’s go out for a walk.
In the event that our team wins, there will be a big celebration.
Send us a message in case you have any difficulty. Suppose (Supposing) we can’t get enough food , what shall we do?
Provided/Providing (that) you give me a receipt , I will pay the rent.
3、表示“考虑到”：given /granted(that)[正式用法], assuming (that),
Given that x=y, then n (x + a) = n (y + a) must be also true.（多用于论证）
4、表示“除非”：unless (=if not)
Let’s go out for a walk unless you are too tired.
5、表示“一旦”：once
Once (=If once) you smoke , you can’t give up smoking.
Once she begins to cry, there is no stopping her.
6、各种复杂介词表示“条件是”：on condition that，on the understanding that, on the assumption/ supposition that, with the proviso/stipulation that, in case of, in the event of等。例如：
I will give him anything he wants on condition that he will show good manners.
Dial 119 in case of fire.
不用连词引导的条件从句
Were I a bird, I would fly to you.（虚拟语气）
Work hard, and you will succeed. (祁使语气)
You do it again, I’ll kill you. (口语体)
A few days’ rest and you will be all right again. (名词+and)
Nothing venture, nothing have. (没有主语和动词) Time permitting, we will go traveling.（分词独立主格结构）
在口语中，真实条件句广泛使用，人们通常用于表示对话语的态度（即起评注性状语作用）。例如：
If you don’t mind, I’d like to think about that for a bit. If I remember rightly , I think I have seen you somewhere.
Take another cup, if you please.
4.2让步从句(Clause of Concession)
让步是对比的一个特殊变体，表达的意义是 “Yes,
but…”，使用让步连接词时，说话人/作者希望表达在承认一个命题正确和确信另一个命题也正确的情况下，削弱第一个命题的重要性，主句中的意思往往是最重要的中心意思，正是让步连接词能让读者或听者做出这样的推论。它有“虽然，尽管，即使”之意，主要由以下引导词构成：
1、 though, although
Although it’s raining, they are still working in the field.
He still works hard though he is very old.
Though the sore be healed, yet a scar may remain.
▲注意：当有though, although 时，后面的从句不能有but ，但是though 和yet 可连用。例如：
Though he is rich, yet he is not happy.
though 还可以用做副词，放在句末。例如：
It was hard work; I enjoyed it, though . = It was hard work, but I enjoyed it.
2、ever if, even though“即使”
We’ll make a trip even though the weather is bad.
3、whether … or … “不管……都”
Whether you believe it or not, it is true.
4、“no matter + 疑问词(what, who, when, where, which, how )”或“疑问词+后缀ever ( whatever, whoever, whenev er, wherever, whichever, however ) ”
No matter what happened, he would not mind.
Whatever happened , he would not mind.
No matter what I say or how I say it, he always thinks I’m wrong.
Don’t let them in, whoever (=no matter who) they are.
▲注意：no matter+疑问词不能引导主语从句和宾语从句。
（×）No matter what you say is of no use now.
（√）Whatever you say is of no use now. ( Whatever
you say 是主语从句)
（×）Prisoners have to eat no matter what they’re given. （√）Prisoners have to eat whatever they’re given . （whatever 引导宾语从句）
5、be it ever so/ let it be ever so…(=no matter how…)
Be it ever so /Let it be ever so humble, there is no place like home. (=No matter how humble it may be, …)
The enterprise, be it as small as it may , requires great ability.
Let the consequences be what they may , he remains firm.
6、while, whereas
while 引导的让步从句，一般放在句首，含有前后对照之意：
While we don’t agree we continue to be friends.
whereas 要求两个情境之间有对偶关系：
Some study the secret of longevity, whereas others study the method of killing.
1、 介词短语+名词/如：for, in spite of/ despite/irrespective of/regardless of/notwithstanding the fact
that
For all their differences, the couple were developing an obvious and genuine affection for each other.
In spite of the fact that his father abandoned him when he was still very young, Victor took good care of him after knowing that he was seriously ill in bed.
8、as 引导的让步从句必须使表语或状语（形容词、副词、分词、实义动词等）前置
Young as he was, he knew what was the right thing to do. = Though he was a small child, he knew what was the right thing to do.
Much as I would like to come, I can’t.
Much as she hated cruelty, she couldn’t help
watching the fight.
▲注意：这种用法中，though/that可以替换as, 但although 没有这种用法，句首名词不能带任何冠词，句首如果是实义动词，其他助动词放在主语后，如果实义动词有宾语和状语，要一起放在主语之前。例如：
Child as/that/though he is, he can speak five foreign languages. = Though he is a child, ….
Try hard as he will , he never seems able to do the
work satisfactorily. = Though he tries hard, he never seems…
除when 和whereas 之外，其他让步从句的连词可引导-ing/-ed和无动词从句。例如：
While not wanting to seem obstinate, I insisted on a definite reply.
Even though given every opportunity , they would not cooperate with us.
Though well over eighty , he can walk faster than I can.
方式从句(Clause of Manner)
方式从句与比较从句不同。比较从句通常由as 和than 引导，不修饰动词，常有一些成分省略。而方式从句由as, (just) as…so…，as if，as though，the way等引导，修饰主句中的动词，只在少数情况下有些省略（例如下面方括号中的词）：
Do the work as I have told you [to do it].
Men fear death as (= in the same manner as) children fear the dark.
Food is to men what/as oil is to machine.
As water is to fish, so air is to man.
The meat tastes as if it were bad.
He went in a hurry as though (as if) he had something urgent to do
Sometimes we teach our children the way our parents have taught us.
as…so…结构经常用于谚语中：
As a man lives, so he dies.
As you sow, so you will reap.
As fire tries gold, so does adversity try friendship. As in war, so in love.
As is the father, so is the son.
限制性定语从句与非限制性定语从句的区别
限制性定语从句提供有关主语或宾语的重要信息，起限定作用，与被修饰部分的关系紧密，如果省略该从句会使主句语义表达不完整。例如：
This is the very person that is wanted by the police. He is the man who /that lives next door.
It was a meeting whose importance I did not realize at the time.
非限制性定语从句只是用来对被修饰部分作补充性的说明，与先行词关系比较松散，先行词与从句间可以用逗号隔开，从句可略去：
He will not be able to spend the holiday with his family, which is a big annoyance to him.
The minister, who is to visit our university, is said to be a Qinghua University graduate.
The book , which your sister bought you in Xinhua Bookstore , is very useful in improving your spoken English.
The businessman, whose suitcase has been found by a stranger , has left for Beijing.
如果定语从句的先行词是专有名词或是带有形容词性物主代词(my, his, etc) 或形容词性指示代词(this, that, etc) 作限定词的名词词组，其后的定语从句通常为非限制性的。例如：
The Thames , which is now clean enough to swim in , was polluted for over a hundred years.
My mother , who has been on a visit to Australia, will fly back tomorrow.
All of these books, which have been donated by visiting professors , are to be used by the children in Hope School.
限制性定语从句的先行词只能是名词，代词或名词性词组，而非限制性定语从句的先行词除了是名词及名词性
词组外，还可能是句子的一部分或是整个句子。例如：
They say he plays truant, which he doesn’t. [which指代plays truant]
The meeting was put off till next month, as we hoped.
[as指前面的句子]
下面的表格归纳了前面已提到的两者不同之处： 表一：限制性定语从句与非限制性定语从句的区别
3.2 定语从句中的关系代词
3.2.1 关系代词that, which, who在定语从句中做主语
在限制性定语从句中，who 或that 用于指人，that 或
which 用于指物，它们在定语从句中代替名词性主语或代词性主语，不能省略。例如：
He is the man who/that lives here. [不能说：×He is the man who he lives here.]
The bag which ／that has been put there for a long time belongs to Wang Hong．
3.2.2 who(m), which, that在定语从句中作宾语
表示人的时候用who(m)或that, 它们在从句中代替名词性宾语或宾格代词，作定语从句宾语的whom/that通常可以省略，在口语中常用who 代替 whom 。例如：
He’s the man whom / that I met.
There are some people here who I want you to meet. 表示动物和东西的时候应用which/that:
The pieces of music (that ) he has composed are sung by many pop singers.
Taxes consist of money (that ) people pay to support their government.
They’re the postcards which I sent from America.
3.2.3 who(m), which或 that 作介词的宾语，关系代词可省略。
定语从句的介词的位置非常重要，我们可以说： He is the person to whom I wrote. [非常正式用法] (但不可以说：×to who).
或：He is the person who (m ) I wrote to . /He is the person (whom ) I wrote to.
This is the pan in which I boiled the milk. [非常正式用法]
或：This is the pan which I boiled the milk in. / This is the pan (that/which) I boiled the milk in.
3.2.4 whose + 名词
关系代词whose 是既可用于限制性定语从句，也可用
于非限制性定语从句，在从句中作定语，一般用来指人，代替所有格形容词（my, his, your, her, its等），在从句中当定语，没有阴性、阳性或单数、复数的变化；有时也可指物，指物时可以用of which 代替。例如：
The professor whose daughter teaches you English is Dr. Williams.
The bicycle whose brake was damaged has now been
repaired. =The bicycle, the brake of which was damaged , has now been repaired.
Edison is a great inventor whose fame is world-wide.
3.2.5 that 的用法
1、that 只用于限制性定语从句，既可指人，又可指物，在句中用做主语或宾语。（见3.2.1、3.2.2）
2、当先行词是all ，much ，little, the one, anything, something, nothing, everything, none等不定代词时，关系代词只用that 。例如：
There is little that can be done about it.
That's all that I knew about it.
Is there anything that I can do for you?
Have you done everything that is assigned to you?
3、先行词被形容词最高级以及first, last, any, only, few, much, no, some, very等词修饰时，关系代词只用that 。例如：
It is the most interesting film that I’ve ever read.
The best thing that he could do at present is to leave. This is the first time that he has been there.
She is the only one that has finished her task on time. At the very beginning, we have just too much work that needs to be done.
4、在there be 句型中，只用that, 不用which 。例如：
There are some people that I’d like to introduce to you .
There is a very interesting story that every child
would like to listen to.
5、先行词既有人，又有物时，用that 。例如：
A victim is a person, animal or thing that suffers pain, death, harm, etc.
The man and his dog that were napping outside the room were photographed by the journalist.
6、在“It is + 名词 + 定语从句1 + 定语从句2”的强调结构中，从句2要用 that 。例如：
It is always the mouth which talks too much that incurs troubles. （言多必失。）
It is only a man who is quite experienced that can fulfill this task.
3.2.6 which 的用法
1、which 一般只用于指物(a)，有时也用来指性别不明的婴儿(b)。例如：
a: The tiles which fell off the roof caused serious damage.
b: The baby which the nurse has just brought in is John’s child.
2、如果指物的关系代词紧跟在介词后面，只能用which ，不能用that 。例如：
This is the house in which she spent her childhood. The agency from which we bought our tickets is bankrupt.
3、引导非限制性定语从句时，用来指物替代名词词组。例如：
This book , which has only been reviewed , was published a year ago.
4、替代整个句子或句子的一部分：
The meeting has been put off till next Friday, is good news to them. (指代整个主句)
She said that her son would become a scientist, we thought possible. (指代that 分句)
She is very attentive in class, 指代
整个短语)
3.2.7 as 的用法
1、as 引导限制性定语从句时，常与such 或the same 连用，构成the same…as; such…as结构，as 用于代替指人或物的先行词。例如：
I have never eaten such tasty foods as she cooked me .
Such books as there were on the shelf interested us. I have got into the same trouble as he (has).
试比较 the same…as和 the same…that：
This is the same book as I read last week（. 这和我上周读的那本书是一样的。）
This is the same book that I read last year. （这就是我上周读的那本书。）
如果先行词表示抽象概念，则没有这种区别，例如：
She told me the same story as/that she had told you. I had the same difficulty that/as you had last year.
在as ／so…as结构中，后面的as 也是关系代词，例如： We took as many men as could be permitted to attend the meeting.
You can stay here as long as you like.
Things do not go on as smoothly as we hoped.
2、引导非限制性定语从句
关系代词as 引导非限制性定语从句时，用于代替整个主句，意思是“正如”， 相当于 and this 或 and that。as 从句位置较之which 引导的非限制性定语从句更加灵活，因而as 从句既可以指前面提到的内容，也可以指后面将要提到的内容，which 一般在主句后。例如：
As is mentioned above , this method aims at improving the students’ ability in a more effective way.
The test is cancelled, as you have hoped.
The test, as you have hoped, is cancelled.
A semiconductor material, as the name indicates, has
poorer conductivity than a conductor.
▲注：as 代表前面的整个主句并在从句中做主语时表达的意思应与主句一致，而且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. 例如：
He failed to pass the exam again, as is predicted.
He failed to pass the exam again, which annoyed his mother greatly.
记住以下的as 结构：
as is known to all (众所周知) ，as is often the case (情况常常如此) ，as the name Indicates／suggests (顾名思义) ，as may be imagined (可以想象得出) ，as often happens (这种情况常常发生) ，as has been said before (如前所述) ，as has been pointed out (正如已经指出的) ，as will be shown in ( 将在…中指出) ，as is hoped ( 正如所希望的)
3.2.8 but 的用法
but 用作关系代词相当于who…not，which…not，that…not。but 既可指人，也可指物，常在定语从句中充当主语或宾语。but 本身含“否定”的意思，它前面的主句通常有“否定”的词, 如：(no，not ， little ，few ，hardly 等). but引导的肯定定语从句和否定的主句连用，达到强烈肯定的修饰效果。例如：
There is no mother loves her own children. (=There is no mother does not love her own children.)[主语]
There is scarcely a good movie (=that he has not seen). [宾语]
There is never a friend of. [介词宾语] Who is there commits errors？[but间或也可用在疑问句后]
There is no man but errs . =There is no man who does not err. [主语]
What he saw in those places but was not miserable （but=which was not）(他所到之处，看到的均是凄惨不已的景象。)[主语]
There are very few but admire his talents.（很少有人不赞赏他的才干的。But=who don’t）[主语]
but 结构有时可省略。例如：
(There is)No rule but has exceptions.
(There are）Few books but have a misprint or two.
3.2.9 than 的用法
关系代词than 一般用于含有比较级的句子中，兼有连词和代词的性质。例如：
You spent more money than was intended to be spent. She has done much more work than was required of her .
The question is more complicated than appears on the surface.
3.3 介词 + 关系代词
“介词 + 关系代词”引导的定语从句既可以是限制性定语从句，又可以是非限制性定语从句，“介词+关系代词”在从句中做主语、宾语、状语、定语等，介词的选择则要根据它与其先行词的关系或前后名词、动词等的搭配关系来决定，同时还应该考虑句子在上下文中要表达的意思。
3.3.1“介词 + which ／whom ／whose”
这时应注意介词与句中短语的搭配。例如：
The problem with which I have trouble has now been solved.
Oil , of which there are several different types, is used for many purposes by countries all over the world.
The man, because of whose help the murderer was caught by the police , is coming to our school
tomorrow.
介词放在关系代词之前的形式的定语从句较之将介词至于从句之末的定语从句正式，因此多用于书面语当中，但在口语中有时也会出现；或者将介词后置，或在介词后置后用 that （人、物）／who （人）代替 which ／whom ，并且that 可省略。例如；
Can you lend me a pen or pencil with which I can write ?
Can you lend me a pen or pencil that / which I can write with ?
Can you lend me a pen or pencil (that ) I can write with ?
Who is the man to whom you were talking?
Who is the man whom /that /who you were talking to ?
Who is the man (that ) you were talking to ?
如果介词过长，则不适于后置，例如：
Sound is a tool , by means of which people communicate with each other.
We may be caught by a fire , in case of which we must find ways to escape.
3.3.2“名词 + 介词 + which／whom”引导的定语从句
He referred to a person the name of whom slipped by memory at that moment.
We had a discussion the purpose of which was to find a solution to this problem.
在非限定性定语从句中，of which ／whom 可用来修饰不定代词 all, each, one, many, much, more, most, any, some, a few, a little, none, both, several, the latter, the former等。练习时，应该判断填空的部分为主句的定语从句还是与主句并列的成分。例如：
We have interviewed more than 50 students , only a few of whom gave satisfactory answers to our
questions. [定语从句]
We have interviewed more than 50 students, but only a few of them gave satisfactory answers to our questions. [并列]
Many people came to her graduation party, most of whom were her former classmates. [定语从句]
Many people came to her graduation party, and most of them were her former classmates. [并列]
There are 32 students in our class, up to 20 of whom are from the south. [定语从句]
3.3.4 “介词 + which + 名词”引导的定语从句
which 是一个代表所有关系的关系代词，可用来代表一个名词／代词或句子的一部分，但更多地是来代表整个句子。其中的名词通常是一个抽象名词，如case, fact, state, time, point等。例如：
Water boils at l00℃, at which temperature it changes into gas.
He was about to leave, at which moment I came back home .
Wei Hua spent four years in the United States, during which period she studied law.
Reader's Digest , to which we have just subscribed , has an enormous circulation.
3.4定语从句中的关系副词
关系副词引导的定语从句（限制性／非限制性）在从句中作状语，意思相当于“介词+which”，常见的引导定语从句的关系副词有：where, when和why 等，不常见的如表示时间的关系副词：since, after和before 。
3.4.1 关系副词 where （= at, in which）引导表示地点的定语从句
This is the place where he’d most like to live the rest of his life.
London is the city where she was born.
That is the place where they met for the first time.
在表示“情况、方面、状况”等有地点含义的抽象名词如case, game, spot, point, conditions, situation, circumstances 等作为先行词的定语从句时，也用 where 引导, 其意义相当于 under which。例如：
It’s a kind of game where you can train your eyesight Everyone may face the situation where you have to make a decision yourself.
I’ll show him the point where he failed.
Under the circumstances where food shortage is the most serious problem , we must try our best to seek international aid.
3.4.2 关系副词 when （= at, on, during, in which）引导表示时间的定语从句
I’ll never forget the day when (=on which) I first came to this university.
This is the season when (=in which) most fishers will be very busy.
That is the time when many Americans were out of work .
Most people like to go there in May , when the flowers are in full bloom.
3.4.3 关系副词 why （= for which）引导表示原因的定语从句
Do you know the reason why he left the party early that night?
The reason why she missed the train is that she was held up by an accident.
3.4.4 其他关系副词引导的定语从句
I miss you every day since I came here.
On the day before she got married, her mother handed her the family heirloom.
The month after she took the entrance examination was spent in relaxing herself
3.5 关系代词和关系副词的省略
3.5.1关系代词的省略
1、关系代词which, whom, who, that在定语从句中作直接宾语时可以省略
Here is the man (who/that/whom) you’ve been looking for .
The woman (whom/who/that) I was talking to is our English teacher.
Is there any question (that ) you want to ask me?
2、当 that 在从句中作补语时可以省略
George is not the man (that ) he used to be.
He is all (that ) a teacher should be.
3、在there be结构中出现定语从句，或在定语从句中出现there be结构时，用做主语的关系代词that 可省略
There is a man downstairs (who ) wants to see you.
This is the best dictionary (that ) there is in the library. That’s all (that ) there is to it. (如此而已。)
Have you noticed anything (that ) there is happening in the company?
3.5.2 关系副词的省略
1、当先行词是reason ，而且在定语从句中做原因状语时，关系代词可用why 或that ，可以省略
The reason (why/that) he failed was his laziness.
That is the reason (why ) I did it.
2、当先行词是way ，且在定语从句中作方式状语时，关
系代词可用 in which或that ，可以省略
The way (in which/that) these comrades look at problems is wrong.
That was the way (in which/that) she worked the problem out.
注意：当关系代词在定语从句中做主语时，不省略。例如：
I don’t know the way that/which leads to the top of the mountains .
3、当先行词表示时间时，关系代词可用when 或有时用that ，有时也可以省略
The second time (that ) I saw him was in 1980.
I don’t know the exact time (when/that) the sports meet will take place.
His grandpa still remembers the day (that/when) the city was liberated.
4、当先行词表示地点时，关系代词可用where 或有时用that ，有时也可以省略
This is the village (where/that) the great man spent his childhood.
Do you know the site (where/that) this ancient tomb was discovered.
I know the place (that/where) she lives.
3.6 what 关系代词
3.6.1 “what is（was ）+ 形容词比较级”结构
what 泛指上文或下文，意思是“更……，尤其……”。该结构常为插入语：
She is very intelligent, and what’s more , very hard-working.
Great men are often unknown, or what is worse , misknown.
She decided, what was the only choice , that she
would keep it a secret.
3.6.2 what = 先行词 + 关系词
what 相当于 the thing（s ）which 或 the person（s ）that, 既可以指人，也可指物，意思相当于“……的（人或物）”，此种情况的what 本身已包含先行词，因而其前不能再有先行词。what 在其从句中可以做主语、宾语和表语。例如：
This is what you call fashion?
That is exactly what you are told to do?
Never pretend to be what you are not.
She is what we call an optimist.
3.6.3 “what + 名词” = “all the + 名词 + that”
what 在从句中作定语。例如：
On her death, the old woman gave what property she had to the young man who stayed with her during the last years of her life. (= all the property that)
We will give you what help we can . (= all the help that)
He shared what little water he had with his companions. (= all the little water that)
What poems we have learned at present are about love. (=all the poems that)
3.7 先行词与其定语从句的分割
有时先行词与其定语从句会被其他的一些语法成分割裂开来，如：状语、定语或谓语等。例如：
We have made a number of creative advances in theoretical research of applied science which are up to advanced world levels.
Do you remember one afternoon ten years ago when l came to your house and borrowed a diamond
necklace ?
During the construction, problems often arise which require design changes.
3.8 定语从句与同位语从句的区别（详见2.5.2）
3.9 关系代词与关系副词的判断
3.9. 1谓语动词是否及物
用关系代词还是关系副词完全取决于从句中的谓语动词。从句中如果及物动词后面接宾语，就必须要用关系代词；而不及物动词则要求用关系副词。例如：
The days when we stayed together are unforgettable. （stay 不及物）
I’ll never forget the days which I spent with you in Tokyo .（spend 及物，有宾语）
This is the reason why he did not come that morning. (come不及物动词)
This is the reason which/ that he found to excuse for himself. (find及物动词 )
3.9.2先行词在定语从句中的成分（主、谓、宾、定、状）
先行词表示时间、地点或原因时，就选用关系副词，用when ，where 或why ，在从句中应该是做状语，否则的话则应该用which ／that 等，that 有时可以代替when ，where 或why ，但when ，where 或why 中不能代替that 。例如：
1. Is this museum you visited a few days ago?
A. where B. that C. on which
D . the one
the exhibition was held.
A . where B. that C. on which
D. the one
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 ；而在句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 。
当从句的逻辑主语是some, any, no, somebody, anybody, nobody, something, anything, everything或nothing 时，常用there is来引导。例如：
I don’t want to concentrate on anything there is worrying me.
引导条件从句的连词
引导条件从句的连词比较多，我们可以把它们分为以下几个大类：
1、表示“只要、只有”：as, as (so) far as, as (so) long as, only if, only that, but that：
As (So) long as we don’t lose heart, we’ll find a way to overcome the difficulty.
There’s war in so far as there’s the earth beneath our feet.
But that he is ill, he would stay at home.
2、表示“如果”：if, in case (that), provided/providing (that), suppose/supposing（that ）[仅用在问句中], in the event (that):
If you are not too tired, let’s go out for a walk.
In the event that our team wins, there will be a big celebration.
Send us a message in case you have any difficulty. Suppose (Supposing) we can’t get enough food , what shall we do?
Provided/Providing (that) you give me a receipt , I will pay the rent.
3、表示“考虑到”：given /granted(that)[正式用法], assuming (that),
Given that x=y, then n (x + a) = n (y + a) must be also true.（多用于论证）
4、表示“除非”：unless (=if not)
Let’s go out for a walk unless you are too tired.
5、表示“一旦”：once
Once (=If once) you smoke , you can’t give up smoking.
Once she begins to cry, there is no stopping her.
6、各种复杂介词表示“条件是”：on condition that，on the understanding that, on the assumption/ supposition that, with the proviso/stipulation that, in case of, in the event of等。例如：
I will give him anything he wants on condition that he will show good manners.
Dial 119 in case of fire.
不用连词引导的条件从句
Were I a bird, I would fly to you.（虚拟语气）
Work hard, and you will succeed. (祁使语气)
You do it again, I’ll kill you. (口语体)
A few days’ rest and you will be all right again. (名词+and)
Nothing venture, nothing have. (没有主语和动词) Time permitting, we will go traveling.（分词独立主格结构）
在口语中，真实条件句广泛使用，人们通常用于表示对话语的态度（即起评注性状语作用）。例如：
If you don’t mind, I’d like to think about that for a bit. If I remember rightly , I think I have seen you somewhere.
Take another cup, if you please.
4.2让步从句(Clause of Concession)
让步是对比的一个特殊变体，表达的意义是 “Yes,
but…”，使用让步连接词时，说话人/作者希望表达在承认一个命题正确和确信另一个命题也正确的情况下，削弱第一个命题的重要性，主句中的意思往往是最重要的中心意思，正是让步连接词能让读者或听者做出这样的推论。它有“虽然，尽管，即使”之意，主要由以下引导词构成：
1、 though, although
Although it’s raining, they are still working in the field.
He still works hard though he is very old.
Though the sore be healed, yet a scar may remain.
▲注意：当有though, although 时，后面的从句不能有but ，但是though 和yet 可连用。例如：
Though he is rich, yet he is not happy.
though 还可以用做副词，放在句末。例如：
It was hard work; I enjoyed it, though . = It was hard work, but I enjoyed it.
2、ever if, even though“即使”
We’ll make a trip even though the weather is bad.
3、whether … or … “不管……都”
Whether you believe it or not, it is true.
4、“no matter + 疑问词(what, who, when, where, which, how )”或“疑问词+后缀ever ( whatever, whoever, whenev er, wherever, whichever, however ) ”
No matter what happened, he would not mind.
Whatever happened , he would not mind.
No matter what I say or how I say it, he always thinks I’m wrong.
Don’t let them in, whoever (=no matter who) they are.
▲注意：no matter+疑问词不能引导主语从句和宾语从句。
（×）No matter what you say is of no use now.
（√）Whatever you say is of no use now. ( Whatever
you say 是主语从句)
（×）Prisoners have to eat no matter what they’re given. （√）Prisoners have to eat whatever they’re given . （whatever 引导宾语从句）
5、be it ever so/ let it be ever so…(=no matter how…)
Be it ever so /Let it be ever so humble, there is no place like home. (=No matter how humble it may be, …)
The enterprise, be it as small as it may , requires great ability.
Let the consequences be what they may , he remains firm.
6、while, whereas
while 引导的让步从句，一般放在句首，含有前后对照之意：
While we don’t agree we continue to be friends.
whereas 要求两个情境之间有对偶关系：
Some study the secret of longevity, whereas others study the method of killing.
1、 介词短语+名词/如：for, in spite of/ despite/irrespective of/regardless of/notwithstanding the fact
that
For all their differences, the couple were developing an obvious and genuine affection for each other.
In spite of the fact that his father abandoned him when he was still very young, Victor took good care of him after knowing that he was seriously ill in bed.
8、as 引导的让步从句必须使表语或状语（形容词、副词、分词、实义动词等）前置
Young as he was, he knew what was the right thing to do. = Though he was a small child, he knew what was the right thing to do.
Much as I would like to come, I can’t.
Much as she hated cruelty, she couldn’t help
watching the fight.
▲注意：这种用法中，though/that可以替换as, 但although 没有这种用法，句首名词不能带任何冠词，句首如果是实义动词，其他助动词放在主语后，如果实义动词有宾语和状语，要一起放在主语之前。例如：
Child as/that/though he is, he can speak five foreign languages. = Though he is a child, ….
Try hard as he will , he never seems able to do the
work satisfactorily. = Though he tries hard, he never seems…
除when 和whereas 之外，其他让步从句的连词可引导-ing/-ed和无动词从句。例如：
While not wanting to seem obstinate, I insisted on a definite reply.
Even though given every opportunity , they would not cooperate with us.
Though well over eighty , he can walk faster than I can.
方式从句(Clause of Manner)
方式从句与比较从句不同。比较从句通常由as 和than 引导，不修饰动词，常有一些成分省略。而方式从句由as, (just) as…so…，as if，as though，the way等引导，修饰主句中的动词，只在少数情况下有些省略（例如下面方括号中的词）：
Do the work as I have told you [to do it].
Men fear death as (= in the same manner as) children fear the dark.
Food is to men what/as oil is to machine.
As water is to fish, so air is to man.
The meat tastes as if it were bad.
He went in a hurry as though (as if) he had something urgent to do
Sometimes we teach our children the way our parents have taught us.
as…so…结构经常用于谚语中：
As a man lives, so he dies.
As you sow, so you will reap.
As fire tries gold, so does adversity try friendship. As in war, so in love.
As is the father, so is the son.