Simple sentence
Compound sentence
Complex sentence
从句：名词性从句（主语从句，宾语从句，表语从句，同位语从句）
形容词性从句(定语从句)
副词性从句（状语从句）
英语中六大从句用法总结
在句子中起名词作用的各种从句，统称为名词性从句
1.主语从句subjective clause
一般由what, who, which, why, how, when, which, whether…or…等引导，如果从句较长，谓语又较短，可用it作形式主语，而将从句放在句末。常见的句型有：
It is self-evident that… 很明显的是
It goes without saying that… 不用说
It is asserted that．．．有人主张……
It is believed that．．．据信……
It is generally considered that．．．人们普遍认为……
It is hoped that．．．人们希望……
It is reported that．．．据报道……
It is said that．．．据说……
It is supposed that．．．据推测．．．
It is well-known that．．．众所周知……
It must be admitted that．．．必须承认……
It cannot be denie d that… 不可否认……
It must be pointed out that．．．需指出的是……
It was told that．．．据传……
It will be said that．．．有人会说……
It follows that… 由此可见
It is inappropriate that… ……是不合适的
2)what引导的主语从句表示“...的东西时”，一般不用it作形式主语。
What we lack is experience.
3)what, who, when, why, whether等词含有各自的疑问意义，但它们引导的主语从句，都用陈述语序。
How the plan is to be carried out should be discussed again.
I did know why I felt like crying.
2.宾语从句objective clause
1）宾语从句可位于及物动词、介词和某些形容词后。连词that常可省略。介词后一般接疑问词引导的宾语从句。in
that(因为),except that(除了),but that(只是）已构成固定搭配，其他介词后一般不接that引导的宾语从句。
*I promised that I would change the situation.
*All this is different from what American young people would say about friendship.
*He is certain that watching so much television is not good for children.
*This article is well-written except that it is a bit too long.
Compliment
2)宾语从句后如有宾补，要用形式宾语it来代替，而把宾语从句移至宾补之后。
He has made it clear that he would not change his mind.
3)在think, believe, suppose, expect等动词后的宾语从句中，如果谓语是否定的，一般将否定词移至主句谓语上，宾语从句则变成肯定形式。
He didn't think that the money was well spent.
2. 表语从句Predictive clause
Linking verb
表语从句出现在结构为“主语+系动词+表语从句”的句子中。表语从句除可用that, what, when, why, whether, how等引导外，还可由because, as if(though)等引导。that常可省略。如主句主语为reason,只能用that引导表语从句，不可用because.
Perhaps the most important thing to remember is that there is no one common type of life in America.
The reason why so many people died there is that there were not enough food supplies.
It looks as if successful international cultural communication will make the world smaller.
4.同位语从句appositional clause
同位语从句用于对前面出现的名词作进一步说明，一般用连词that引导，由于先行名词的意义不同，也可用whether, who, when, where, what, why, how等引导。常见的先行名词有
fact,idea,belief,news,hope,conclusion,evidence,suggestio n,order,problem,report,decision.有时由于谓语较短，将同位语从句位于谓语之后。
She finally made the decision that she would join the fashion show.
I had no idea how many books I could borrow at a time.
The news came that their team had won the championship.
5.定语从句attributive clause
定语从句所修饰的先行词可以是名词或代词，也可以是一个句子。定语从句通常位于先行词之后，由关系代词或关系副词引导。
*限制性定语从句
限制性定语从句修饰先行词，对先行词起修饰作用，紧接先行词之后，无逗号，若省去，原句意思不完整。引导定语从句的关系代词有who, whom, whose, which, that等。who, whom, whose用于指人，whose有时也可指物，相当于of which；which用于指物；that既可指人也可指物，但只用于限制性定语从句中。关系代词除了引导定语从句，替代先行词外，还在从句中担任主语、宾语、定语等。
The computers and cables which make up the Internet are owned by people and organizations.
Those who live alone or who are sick may have trouble in getting close to other people.
The girl whose parents died in an accident is living with her grandmother.
1)当先行词是all, anything, everything, something, nothing 等不定代词或先行词前有first, last, any, few, much, some, no, only以及形容词最高级修饰时，只能用关系代词that引导从句。
That is all that I've heard from him.
He's the first person that I'm going to interview this afternoon.
2)关系代词的省略
在从句中作宾语的关系代词常可省略。关系代词紧跟介词，作介词宾语时不可用that，只可用which或whom引导从句，并且不可省略，但当介词位于宾语从句句末时，作为介词宾语的关系代词仍可用that，也可省略。
This is one of those things with which we have to put up.
This is one of those things (which\that) we have to put up with.
3)引导定语从句的关系副词有when, where, why等。关系副词在从句中作状语，意义上相当于一个“介词+which”的结构。Even in comic books where(=in which) there are no words, the stories are fully expressed through the drawings.
No one knows the reason why(=for which) he was so angry that day.
*非限制性定语从句
非限制性定语从句既可修饰先行词，也可修饰整个主句，起补充说明作用，与主句之间有逗号隔开，若省去，原句意思不受影响。不可用that引导非限制性定语从句。关系词不可省略。
Every object has a gravitational pull, which is rather like magnetism.
*“介词+which\whom\whose”引导的定语从句
“介词+which\whom\whose”可引导限制性定语从句，也可引导非限制性定语从句，该结构中介词的选择取决于从句谓语动词的固定搭配，或先行词的习惯搭配。
It is written by a person with whom we are all familiar.
The girl to whom you speak is my sister.
*as引导的定语从句
as引导的定语从句主要用于“such...as”及“the same...as”的结构中，代替先行词是人或物的名词。as引导非限制性定语从句时，代替整个主句，从句可位于主句之前、之后或中间。
These are not such problems as can be easily solved.(as
代替先行词problems)
As is mentioned above, no single company or group can control what happens on the Internet.(as代替主语)
6.状语从句adverbial clause
*时间状语从句
引导时间状语从句的从属连词和词组有：
1）when, whenever, while, as, after, before, since, till, until, once等。
We have learnt quite a lot about it since we came here. 2)as soon as, hardly(scarcely)...when, no sooner...than, each(every) time, the moment, immediately(that)等。
As soon as I sent an e-mail message, I received positive responses.
The moment he heard the good news, he jumped with joy.
*地点状语从句
引导地点状语从句的连词是where, wherever.
Wherever she went, she took her little daughter with her.
*原因、结果和目的状语从句
1）引导原因状语从句的从属连词有：because, as, since, now(that),seeing that, considering that, I n that等。Considering that he is a freshman, we must say he is doing well.
2)引导结果状语从句的连词有：so...that, such...that
,so that, that, so等。
Mickey Mouse is so attractive that the children are reluctant to leave.
3)引导目的状语从句的连词有：so that, in order that, for fear that, lest等，从句常使用may, might, can, could, would等情态动词。
We got up early this morning so that we could catch the first bus to the railway station.
*条件和让步状语从句
1）引导条件状语从句的连词和词组有if, unless, as(so) long as, on condition that, in case, provided(providing) that, supposing等。
As long as you have the right equipment, you can use a telephone line to transmit computer data.
2)引导让步状语从句的连词和词组有though, although, whether, even though, even if, no matter what(when, how...),whatever(whenever, wherever, however....)等。though, even if等引导状语从句可转换成含有as的部分倒装结构，具有强调意义。其结构为“形容词（副词、动词、名词）+as+主语+谓语”。
No matter what you may say, I would not change my mind. Young as he is, he is quite experienced in this
work.(=though he is young)
Child as he is, he can speak English fluently.(=though he is a child)
*方式状语从句
引导方式状语从句的连词有as, just as, as if, as though等。as if, as though引导的状语从句中，谓语动词常用虚拟语气，表示与事实相反。
The young man made the experiment just as the teacher had taught him.
Everything went on as usual as if nothing had happened.
从句 从句按其在主句中的句法功能可分为三类: 即名词性从句、形容词性从句(即定语从句)和副词性从句(即状语从句)。 引导从句的词称作关联句. 一、名词性从句 引导这些名词性从句的关联词包括: 从属连词that, if, whether; 连接代词 who,whoever,whom,whomever,which,whichever,what,whatever,wh ose; 连接副词where, when, why, how。 其中, 从属连词只起连接作用, 在从句中不充当任何句法成分, 而连接代词和连接副词既起连接作用, 在从句中又充当一定的成分. That Owen should have married his cousin is not at all surprising. The fact is that he didn't go to the dinner party. I don't know if he will attend the meeting. Have you heard the news that Mary is going to marry Tom? 你听说玛丽要和汤姆结婚的消息了吗?(that引导同位语从句) [提示]
1. 在含有主语从句的复合句中, 为保持句子平衡, 常用it作形式主语,而将真正的主语从句置于句末. It's well-known that water is indispensable to life.(形式主语) 2. 为保持句子平衡, that引导的宾语从句也常用it代替, 而将真正的宾语从句置于主句句末。这常常出现在主句有形容词或分词作宾语补足语的情况下。 He made it quite clear that he preferred to live here. 3. 从属连词whether和if都作“是否…”解, 但if不可引导主语从句和表语 从句。whether可与or(not)连用, 而if不可以。 I don't know whether (if) she is at home. Whether she comes or not makes no difference. 4. that和what引导名词性从句的区别: that在从句中不充当成分,而what在从句中充当一定的成分, 如主语、表语、宾语等。that可省略, what则不可省。 He always means what he says. She suggested (that) he do it at once. 5. 同位语从句大多由从属连词that引导, 常跟在下列名词后面, 如fact, idea, opinion, news, hope, belief等, that不可省。同位语从句一般用来解释说明这些名词的具体含义和内容。 We are familiar with the idea that all matter consists of atoms. The news that we are invited to the conference is very encouraging.
复合句 【语法要点】 复合句是由一个主句加一个或几个从句所构成的句子。从句只用作句子的一个成分，不能独立。根据从句在句子中的作用，可分为名词性从句、定语从句和状语从句三类。 （一）名词性从句 名词性从句包括主语从句、表语从句、宾语从句、同位语从句。其关联词有连接词that、if、whether；疑问代词who、what、which和疑问副词when、where、how、why等。 1.名词性从句句法结构： 从 属 连 词that whether 主 语 从 句 That he will come is certain.（that不可省） Whether she is coming or not doesn’t matter too much. （不能用if） 宾 语 从 句 I think（that）he will be all right in a few days. I went in and asked if（=whether）they had a cheap suit. I wonder whether（不能用if）it is true or not. 表 语 从 句 The fact is（that）I have never been there. The question is whether（不能用if）it is worth doing. 同 位 语 从 句 The fact that she had not said anything surprised all of us. They asked me the question whether the work was worth doing. 连接代词 that who whom whose which 主 语 从 句 Who will help him is not known. What he said is very important. Which side will win is not clear. 宾 语 从 句 （1）作及物动词的宾语。例如： I really don’t know what he is doing. Do you know who/whom they are waiting for? He asked whose dictionary it was. He can’t tell which method they will use for the experiment. （2）作介词的宾语。例如： Pay attention to what the teacher said. I wondered to whom he had given the letter. 表 语 从 句 That is what he is worried about. The question is who will come here. The question is which team will win the match.
初中英语语法——三大从句汇总 在英语中，主要有三大从句，即名词性从句（包括主语从句，宾语从句，表语从句，同位语从句）、形容词性从句（即定语从句）、副词性从句（即状语从句,包括时间、条件、结果、目的、原因、让步、地点、方式等）。以下是一些基本的从句知识点 A、定语从句专项讲解与训练 一、定语从句概念 定语从句（attributive clause），顾名思义，就是一个句子作定语从属于主句。定语一般是由形容词充当，所以定语从句又称作形容词从句。另外，定语从句是由关系代词或关系副词引导的，故又称作关系从句。关系词常有3个作用：1，引导定语从句。2，代替先行词。3，在定语从句中担当一个成分。 定语从句一般放在它所修饰的名词或代词之后，这种名词或代词被称作先行词。请看示例：The woman who lives next door is a teacher. 先行词定语从句 在所有的从句中，算定语从句最难掌握，因为汉语里没有定语从句，汉语里只有定语，而且总是放在名词之前来修饰名词。 二、关系代词引导的定语从句 关系代词代替前面的先行词，并且在定语从句中充当句子成分，可以作主语、宾语、定语等。常见的关系代词有：who, that, which。它们的主格、宾格和所有格如下表所示： 格先行词主格宾格所有格 人who whom whose 物which which whose 、of which 人、物that that — （一）关系代词who, whom和whose的用法 1）who代替人，是主格，在定语从句中作主语。例如： An architect is a person who designs buildings. 建筑师是设计房屋的人。 I will never forget the teacher who taught us chemistry in the first year of my senior middle school. 我将永远不会忘记在高一时教我们化学的那位老师。 Anyone who wants to apply for this job must send us the resume by email first. 想应聘这个职位的任何人都必须先通过电子邮件向我们发送简历。2）whom代替人，是宾格，在定语从句作宾语，在非正式英语常可省略。例如：Do you know the gentleman whom we met in the school library yesterday? 昨天我们在学校图书馆里遇到的那位先生你认识吗？ This is the student whom my father taught ten years ago. 这是我爸爸十年前教的学生。 The girl who I saw is called Mary. 我见到的那个女孩名叫玛丽。（在非正式 英语中，主格who代替了宾格whom，亦可省略） 3）whose一般代替人，有时亦可代替物，是所有格，在定语从句作定语。例如：The girl student whose father is a senior engineer used to study abroad.
中考英语三大从句练习及答案解析 定语从句： （一）基础：引导词---who, which, that, whom, 练习1.I like cities___________are quiet and clean. 2.I prefer students _________are hard- working. 3.I hate TV shows _________ are noisy and boring. 4.The music __________ is gentle and quiet attracts me a lot. 5.The food __________tastes delicious is not always healthy. 6.Those boys ___________ are playing basketballs over there are from Class Fifteen. 7.The books ____________ are written by Lu Xun are worth reading. 8.The town ___we visited last week is much larger than before.9.The book ___ he bought is very interesting. （二）特例：只用that的情况 1先行词被___________或___________所修饰，或本身是______________________时，只能用 that， 2.被修饰的先行词为 ________________________________________________等不定代词时, 只能用 that. 3.先行词被 _____________________________________________等词修饰时，只能用 that，而不用which。 4.先行词里同时含有______________________，如I can remember well the persons and some pictures that I saw in the room. 5. 以______________________引导的特殊疑问句，只能用that.如： Who is the girl that is crying? 练习1. I am interested in everything___ is about the 2006 World Cup. 2. Is there anything___I can do for you? 3. This is the very bike ______I lost 4.To my surprise, he gave me nothing __ I need. 5.This is the best dictionary __ I have ever used. 6. He was the first person _______passed the exam. 7.He talked happily about the men and books________interested him greatly. （三）whose 1. The student ______father works in the factory is sitting there. 2. I like the rooms ______windows face south. 3. This is the desk ______legs were broken. 4The woman ___ umbrella you took is angry about it.5.. 6The banana __skin is green can’t be eaten.7That tall tree _ leaves are yellow is very old. （四）从句谓语单复数由先行词确定，时态由从句时间状语决定，不必跟主句保持一致。 1-He is one of the boys who ____ (doesn’t, don’t) finish doing homework. 2-I like films which ____(be) exciting and interesting. 3- 4-That boy who _____(run) fastest is from our class. 5Those boys who ____ playing the guitar are from our school. (be) 6The trees which _____ (be) watered yesterday belong to them. 7The man who ____ over there is our teacher.(stand) 8Those boys who ____ playing the guitar are from our school. (be) 9Mr. Brown is one of the foreign experts _______ _________ (work) in China. 10I’m one of the boys ______ ________(like) English best. (五)“介词＋关系代词”注意：介词的选用要考虑： A.与先行词的搭配关系 1）I will never forget the day __________ I joined the army. 2) I will never forget the days ______ I worked here. 3) I will never forget the year ____________ my son went to college.
中考从句讲与练 定语从句： （一）基础：引导词---who, which, that, whom, 练习1.I like cities___________are quiet and clean. 2.I prefer students _________are hard- working. 3.I hate TV shows _________ are noisy and boring. 4.The music __________ is gentle and quiet attracts me a lot. 5.The food __________tastes delicious is not always healthy. 6.Those boys ___________ are playing basketballs over there are from Class Fifteen. 7.The books ____________ are written by Lu Xun are worth reading. 8.The town ___we visited last week is much larger than before.9.The book ___ he bought is very interesting. （二）特例：只用that的情况 1先行词被___________或___________所修饰，或本身是______________________时，只能用 that， 2.被修饰的先行词为 ________________________________________________等不定代词时, 只能用 that. 3.先行词被 _____________________________________________等词修饰时，只能用 that，而不用 which。 4.先行词里同时含有______________________，如I can remember well the persons and some pictures that I saw in the room. 5. 以______________________引导的特殊疑问句，只能用that.如： Who is the girl that is crying? 练习1. I am interested in everything___ is about the 2006 World Cup. 2. Is there anything___I can do for you? 3. This is the very bike ______I lost 4.To my surprise, he gave me nothing __ I need. 5.This is the best dictionary __ I have ever used. 6. He was the first person _______passed the exam. 7.He talked happily about the men and books________interested him greatly. （三）whose 1. The student ______father works in the factory is sitting there. 2. I like the rooms ______windows face south. 3. This is the desk ______legs were broken. 4The woman ___ umbrella you took is angry about it.5.Here comes a girl ___ handwriting is the best . 6The banana __skin is green can’t be eaten.7That tall tree _ leaves are yellow is very old. （四）从句谓语单复数由先行词确定，时态由从句时间状语决定，不必跟主句保持一致。 1-He is one of the boys who ____ (doesn’t, don’t) finish doing homework. 2-I like films which ____(be) exciting and interesting. 3-Children who often ____(eat) junk food are easy to become fat and unhealthy. 4-That boy who _____(run) fastest is from our class. 5Those boys who ____ playing the guitar are from our school. (be) 6The trees which _____ (be) watered yesterday belong to them. 7The man who ____ over there is our teacher.(stand) 8Those boys who ____ playing the guitar are from our school. (be) 9Mr. Brown is one of the foreign experts _______ _________ (work) in China. 10I’m one of the boys ______ ________(like) English best. (五)“介词＋关系代词”注意：介词的选用要考虑： A.与先行词的搭配关系 1）I will never forget the day __________ I joined the army. 2) I will never forget the days ______ I worked here. 3) I will never forget the year ____________ my son went to college. B. 与谓语动词的搭配习惯 1）Have you found the book ________I paid 29 dollars? 2）Have you found the book ________I spent 29 dollars? 3)Have you found the book _____________we learnt a lot? 4) Have you found the book _______she often talks? 关系副词的用法 练习：1. It must be a good place ________________we can do a lot of exercise.
英语语法: 英语从句完全汇总 一.主语从句 主语从句是在复合句中充当主语的从句，通常放在主句谓语动词之前或由形式主语it 代替，而本身放在句子末尾。 1. It 作形式主语和it引导强调句的比较 It 作形式主语代替主语从句，主要是为了平衡句子结构，主语从句的连接词没有变化。而it引导的强调句则是对句子某一部分进行强调，无论强调的是什么成分，都可用连词that。被强调部分指人是也可用who/whom。例如： It is a pity that you didn’t go to see the film. It doesn’t interest me whether you succeed or not. It is in the morning that the murder took place. It is John that broke the window. 2. 用it 作形式主语的结构 (1) It is +名词+从句 It is a fact that …事实是… It is an honor that …非常荣幸 It is common knowledge that …是常识 (2) it is +形容词+从句 It is natural that…很自然… It is strange that…奇怪的是… (3) it is +不及物动词+从句 It seems that…似乎… It happened that…碰巧… (4) it +过去分词+从句 It is reported that…据报道… It has been proved that…已证实… 3. 主语从句不可位于句首的五种情况 (1) if 引导的主语从句不可居于复合句句首。 (2) It is said , (reported) …结构中的主语从句不可提前。例如： It is said that President Jingo will visit our school next week. (right) That President Jiang will visit our school next week is said. (wrong) (3) It happens…, It occurs…结构中的主语从句不可提前。例如： It occurred to him that he failed in the examination. (right) That he failed in the examination occurred to him. (wrong) (4) It doesn’t matter how/whether …结构中的主语从句不可提前。例如： It doesn’t matter whether he is wrong or not. (right) Whether he is wrong or not doesn’t matter. (wrong) (5) 含主语从句的复合句是疑问句时，主语从句不可提前。例如： Is it likely that it will rain in the evening? (right) Is that will rain in the evening likely? (wrong) 4. What 与that 在引导主语从句时的区别 What 引导主语从句时在句时在从句中充当句子成分，如主语.宾语.表语，而that 则不
定语从句 一、基本概念： 定语： 定语从句： Do you know the man who spoke at the meeting just now That is the house where he lived ten years ago. 引导词：关系词 关系代词有：that, who, whom, whose, which; 在从句中充当： 关系副词有：when, where, why. 在从句充当： 先行词： 定语从句中引关系词的作用： 二、关系词的用法： （一）关系代词的用法： 1． He is the man lives next door. The train has just left is for Shenzhen. 2． The man ________ we have just seen is a famous writer. Where is the book ___________I bought last week （二）关系副词的用法： 1． I still remember the time ________I first became a college student. Do you know the date __________Lincoln was born
(三) 使用关系副词应注意下列几点： 1．这三个关系副词在意义上都相当于一定的介词+which结构： when = on (in, at, during…) + which; where = in (at, on…) + which; why = for which. 如： I was in Beijing on the day when (=on which) he arrived. The office where (=in which) he works is on the third floor. This is the chief reason why (=for which) we did it. 2．当先行词是表时间的time, day等和表地点的place, house等时，一定要注意分析从句的结构，如果缺少主语或宾语时，关系词应该用which或that, 缺少时间状语或地点状语时，才能用when或where，试比较： I’ll never forget the day _________ my hometown was liberated. I’ll never forget the days____________we spent together last summer. His father works in a factory____________radio parts are made. His father works in a factory______________makes radio parts. 三．限制性定语从句与非限制性定语从句 1．限制性定语从句 This is the telegram which he refers to. Is there anything (that) I can do for you 2．非限制性定语从句 This note was left by Tom, who was here a moment ago. As a boy, he was always making things, most of which were electric.
一. 宾语从句object clause： 一. 定义definition： 在句子中起宾语作用的从句叫做宾语从句。 二. 连接词connections： that: I think that you can pass the exam. Whether/if: I don’t know what the word means. “Wh”: I don’t know what the word means. I don’t know where he found the book. 只用whether的情况： 1. 与or not连用： I don’t know whether it’s raining or not. 2. 与动词不定式连用： He doesn’t know whether to accept the invitation. 3. 连接词前有介词时： It depends on whether he is coming. 三. 时态tenses: 1. 主句是一般现在时态，从句根据实际情况而定(各种时态均可) She wants to know what he has done for the exam. 2.主句是一般过去时态，从句用相应的过去的时态。 1）She said that she was a student. 2）She said that she would fly to Japan in a week. 3）She said that she had finished her homework already. 3. 如果宾语从句说的是客观真理、自然现象或事实时，这时宾语从句要用一般现在时态。 The teacher said that the earth goes round the sun. 二. 定语从句Attributive clause： 1.定义：在复合句中修饰名词、代词的从句叫定语从句 2.先行词指人who /that 先行词指物which/ that 3. 定语从句一般紧跟被修饰的名词或代词（即先行词）后 4.关系代词代替先行词在句子中担当成分，所以从句中不可再出现其他代替先行词的代词 5.翻译方法“…. 的” Eg. 1. Yesterday we bought a book which is really hard to understand. 2. The students who are from Maple Leaf School like learning English. Whom: 先行词指人，则代替先行词在定语从句中充当宾语（包括介词的宾语）, 与who的区别是如果前面带介词则必须用whom 1.This is the teacher whom\who we like best. 2. I don’t like the boy to whom you are talking. Whose : 指人或物，作定语，表示“…的” eg: Harry is the boy whose mother is our math teacher.
初中英语语法宾语从句讲解 小口诀： 宾语从句三注意，时态语序引导词；主句一般现在时，从句不需受限制； 主句一般过去时，从句须用相应时；陈述转化that引，一般疑问用if/whether, 特殊问句疑问词，引导词后陈述式。 一．基本讲解来源：直接引语变间接引语 概念:在句中担当宾语的从句叫宾语从句。 Eg: He said,“I am good at drawing”. He said he was good at drawing. (动词宾语) 1.引导词 (1) that引导宾语从句时，通常用陈述句充当, that可省略。 Eg: She said,“I want to go there ”She said (that) she wanted to go there. (2) whether 或if 引导的宾语从句,由一般疑问句/选择疑问句充当，陈述语序。 Eg: “Are you interested in geography?” she said. She asked if/whether I was interested in geography. I wonder if /whether she has told the new to Li Lei . I’m not sure whether he will come or not. 注意：一般情况下，whether 和if 可以互用，但有些情况例外 a. 介词短语后只用whether 不用if eg: We are talking about whether we'll go on the panic. b. 引导词与动词不定式或or not 连用时，只用whether. eg:I can?t say whether or not he will come on time c. if当如果讲时,引导的是条件状语从句，表示‘如果’，不能用whether. Eg: If you want to be a good teacher, it will take times. Whether you can succeed depends on how much effort you pay. (3).特殊疑问词引导宾语从句时，不可省略，陈述句语序。 特殊疑问词为：how , when, where, why ,which whose. E.g. …What do you want?? He asked. He asked me what I wanted. I have no idea where he is now. I don?t know how to deal with it. He asked whose handwriting is the best in the class. 2.宾语从句时态 a.主句为一般现在时，从句不受主句的限制 eg: Do you know if/whether he has seen the film? I?m sorry to hear that your father is ill. She says she is going to go to Beijing next week. He tells me that his sister came back yesterday. b.当主句是一般过去时，从句用过去的相应某种时态 She didn?t know why the boy was late again. (过去一般) I didn't know if/whether he had seen the film.（过去完成） I wondered when she was going to America.（过去将来） 注意：当主句是一般过去时，而从句表示的是客观真理，自然现象，科学原理，格言等，从句仍然要用一般现在时。例如： Eg: He said （that the earth moves round the sun. / that light travels much faster than sound.）The teacher told us （seeing is believing.）
高中英语语法定语从句总复习 郴州资兴三中李俊才 定义：用来说明主句中某一名词或代词（有时也可说明整个主句或主句中一部分）而起定语作用的句子叫 作定语从句。 一、关系带词引导的定语从句 1. 关系代词用来指代先行词是人或物的名词或代词 句子成分用于限制从句或非限制性从句只用于限制性从句 代替人代替物代替人或物主语Who which 主语Whom which that 宾语Whose (=of whom) Whose (=of which) that 例１：This is the detective who came from London. 例２：The book which I am reading is written by Tomas Hardy. ２．关系代词的用法 (1) 如果先行词是all, much, anything, something, nothing, everything, little, none等不定代词，关系代词一般只用that，不用which。例如： All the people that are burst into tears.（所有人都迸出眼泪。） (2) 如果先行词被形容词最高级以及first, last, any, only, few, most, no, some, very等词修饰，关系代词常用that,不用which, who，或whom。 (3) 非限制性定语从句中，不能用关系代词that,作宾语用的关系代词也不能省略。 There are about seven million people taking part in the election, most of whom、are well educated. (4) which还有一种特殊用法，它可以引导从句修饰前面的整个主句，代替主句所表示的整体概念或部分 概念。在这种从句中，which可以作主语，也可以作宾语或表语，多数情况下意思是与and this 相似，并可以指人。例如： He succeeded in the competition, which made his parents very happy. (5) that可指人或物，在从句中作表语，（指人作主语时多用who）仅用于限制性定语从句中。
在英语中，主要有三大从句，即名词性从句（包括主语从句，宾语从句，表语从句，同位语从句）、形容词性从句（即定语从句）、副词性从句（即状语从句,包括时间、条件、结果、目的、原因、让步、地点、方式等）。 以下是一些基本的从句的语法知识点 A、定语从句专项讲解与训练 一、定语从句概念 定语从句（attributive clause），顾名思义，就是一个句子作定语从属于主句。定语一般是由形容词充当，所以定语从句又称作形容词从句。另外，定语从句是由关系代词或关系副词引导的，故又称作关系从句。 定语从句一般放在它所修饰的名词或代词之后，这种名词或代词被称作先行词。请看示例： The woman who lives next door is a teacher. 先行词定语从句 在所有的从句中，算定语从句最难掌握，因为汉语里没有定语从句，汉语里只有定语，而且总是放在名词之前来修饰名词。 二、关系代词引导的定语从句 关系代词代替前面的先行词，并且在定语从句中充当句子成分，可以作主语、宾语、定语等。常见的关系代词有：who, that, which。它们的主格、宾格和所有格如下表所示： 格 先行词主格宾格所有格 人who whom whose 物which which whose of which 人、物that that — （一）关系代词who, whom和whose的用法 who代替人，是主格，在定语从句中作主语。例如： An architect is a person who designs buildings. 建筑师是设计房屋的人。 I will never forget the teacher who taught us chemistry in the first year of my senior middle school. 我将永远不会忘记在高一时教我们化学的那位老师。 Anyone who wants to apply for this job must send us the resume by email first. 想应聘这个职位的任何人都必须先通过电子邮件向我们发送简历。 whom代替人，是宾格，在定语从句作宾语，在非正式英语常可省略。例如： Do you know the gentleman whom we met in the school library yesterday? 昨天我们在学校图书馆里遇到的那位先生你认识吗？ This is the student whom my father taught ten years ago. 这是我爸爸十年前教的学生。 The girl who I saw is called Mary. 我见到的那个女孩名叫玛丽。（在非正式英语中，主格who代替了宾格whom，亦可省略） whose一般代替人，有时亦可代替物，是所有格，在定语从句作定语。例如： The girl student whose father is a senior engineer used to study abroad. 其父是一位高级工程师的那个女学生过去在国外留学。 Do you know the name of the hotel whose window we can see here? 我们这儿能看到窗户的那个宾馆叫什么名
初中英语三大从句汇总讲解 从句是相对于主句而言的，即它是从属于某一个主句，而不能单独作一个句子。在英语中主要有三大从句，即： 1. 名词性从句 2. 定语从句 3. 状语从句。 1）主语从句用作主语，如： That the earth is round is true. 地球是圆的是真实的。 2）宾语从句用作宾语。如： Do you know where he lives? 3）表语从句用作表语，如： My opinion is that you should not go alone. 我的意见是你不应单独前往。 4）同位语从句用于解释说明前面的名词。如： The fact that the earth is round is true. 地球是圆的的事实是真实的。 5）定语从句相当于一个形容词，用于修饰前面的名词。如： The student who answered the question was John. 回答问题的学生是John. 6）状语从句相当于一个副词，如：
When it rains, I usually go to school by bus. 天下雨时，我通常坐公共汽车上学。 If he comes tomorrow, you will see him. 如果他明天来，你就可以看见他。。要注意在状语从句中有一个规则是“主将从现”，即主句是将来时，则从句要用一般现在时表示将来。 He returned home to learn his daughter had just been engaged.他回家后得知女儿刚刚订婚了。，find，see，hear，to be told，make等具有界限含义的动词。） You must speak louder so that /in order that you can be heard by all. 你必须大声说话，才能让所有人听到你说话。 Since /As the weather is so bad，we have to delay our journey. 天气那么糟，旅行推迟了。，seeing that ，now that ，considering that 等引导。） Though/Though he was worn out，he kept on working. 虽然他已经精疲力竭了，但仍然继续工作。 Where I live there are plenty of trees. 我住的地方树很多。 As water is to fish, so air is to man. 我们离不开空气，犹如鱼儿离不开水。as…so…，as if，as though引导。）主句和从句的划分方法是相同的。句子的成分从谓语动词处来划分比较容易。谓语动词前面的部分是主语，后面常接宾语，修饰谓语动词的是状语，修饰主语、宾语的是定语，若谓语是系动词，则系动词后的部分是表语。如：