按一般说法，可分为三大类14种从句。
一,名词性从句
1主语从句Whether it's right or not remains to be seen.
2宾语从句I wonder whether it's right or not.
3同位语从句This is a question whether it's right or not.
4表语从句The question is whether it's right or not.


二,定语从句
1限定性定语从句She is the student who can speak English well.
2非限定性定语从句She is the student,who can speak English well.


三,状语从句
1时间状语从句The fact will come out when he comes here.
2地点状语从句You can go wherever you like.
3原因状语从句Pay more attention to your lessons because you are a student.
4方式状语从句He walks as if he were a king.
5目的状语从句She went to Japan so that she could learn Japanese well.
6结果状语从句She went to Japan so that she learned Japanese well.
7条件状语从句I will understand it if he tells me.
8让步状语从句He knows a lot though he is little.


PART2：经典名词性从句
主语从句(subject clauses)在复合句中起主语作用的从句叫主语从句。引导主语从句的词有从属连词、、关系代词、连接副词等。引导主语从句的关联词有从属连词that、whether，关系代词：who, what, which , whom, whose, whatever, whoever, whomever, whichever；关系副词：when, where, how, why, however, whenever, wherever等。
That you don’t like him is none of my business.你不喜欢她不管我的事。
What he said is true. 他说的是真的。
Do you remember how he arrived almost at the end of the party? 你记得他几乎是在宴会快结束时才到的吗？              This party's really where it's at, man! 啊，这个晚会真棒！
Tell us how you fulfilled the heavy task ahead of schedule.告诉我们,你们是怎样提前完成这一艰巨任务的。
We have reason to believe that the fighting on the border may develop into a full-blown war. (喻)我们有理由相信边境上的冲突可能发展成一场全面战争。
He said that he would come. 他说他要来。
Whether the football game will be played depends on the weather.足球比赛是否举行将视天气而定。




表语从句 用作表语的从句叫作表语从句，它位于主句中的连系动词之后。引导表语从句的词有从属连词that、whether、as though(if)；关系代词who, what, which, whom, whose, whatever, whoever, whomever, whichever等；关系副词when, where, why, how, however, whenever, wherever等。可以接表语从句的连系动词由be, look, remain, seem等。That引导表语从句时，在口语中，间或可以省略。
The trouble is that we are short of money.困难是我们资金短缺。
That is why stone walls are used instead of fences around New England fields.这就是为什么在新英格兰用石头墙而不用栅栏的原因。
At that time, it seemed as if I couldn't think of the right word anyhow.当时,我似乎怎么也想不出一个恰当的字眼来。


宾语从句(object clauses)用作宾语的从句叫做宾语从句。宾语从句的位置与陈述句基本结构中的宾语相同。宾语从句可作谓语动词的宾语，也可以作介词和非谓语动词（动词不定式、动名词、分词）和某些形容词的宾语。宾语从句可以由从属连词that whether、if，关系代词what, who, whose, which和关系副词when、where、how、why等引导。
He said he wanted to go to town. 他说他想去城里。
I hope you'll be better soon.我希望你能很快好起来。
I’m so glad that you were able to come to this party.你能设法抽空出席这个交际会，我很高兴。
I know nothing about it except what I have read in the papers.除了在报上读到的以外,我对这件事一无所知。
Most of the Chinese people usually go to work on the bike except when it rains.除了雨天,大多数中国人一般都骑自行车上班。
He asked me whether she was coming. 他问我，她来还是不来。


同位语从句 用作同位语的从句叫同位语从句。它一般跟在抽象名词fact，idea，news，hope，belief，thought，truth，doubt，suggestion，warning, instruction，reason，information, question等之后，对这些名词进行说明或解释。引导同位语从句的词除连词that，whether外，还有关系代词what, which, who, 以及关系副词how，when，where，why等。
It is a fact that smoking is a danger to health. 吸烟危害健康，这是事实。
I have no idea  what you mean.我一点儿也不明白你的意思。
He made the suggestion that we go by train. 他建议我们坐火车去。
There is no doubt that he is guilty. 毫无疑问，他是有罪的。


PART3：经典定语从句
1.窗户朝南的那间房间是我的。
The room whose window faces south is mine.=The room of which the window faces south is mine.
1. 整座城市躺在废墟中，其中百分子75的工厂和大楼消失不见了。
The whole city, 75% of whose factories and buildings were gone, lay in ruins.
2. 我们公司有2000工人，三分之二是女工。
Our company has 2000 workers, of whom two thirds/ two thirds of whom are women.
3. 那些被困在废墟里的人已经得救了。
Those who were trapped under the ruins finally got rescued.
4. 你们刚才谈论的那场地震好可怕呀！
The earthquake that you were talking about sounded frightening/shocking.=The earthquake about which you were talking sounded frightening.
5. 我的家人都是音乐爱好者，今晚将去看电影。
My family, all of whom are music lovers, are going to the movie tonight.
6. 我们正在看的这幢大楼过去曾经是一家医院。
The building which we are looking at used to be a hospital.
7. 约翰向母亲说起过把他在国外见过的人和城市。
John  once talked to his mom about the people and cities that he had visited abroad.
8. 他是去过伦敦的一位以观光者之一。
He is one of the tourists who have been to London.
9. 他是这些观光者当中唯一去过伦敦的。
He is the only one of the visitors that/who has been to London.
10. 这就是你们上个礼拜参观过的学校吗？
Is this the school that you visited last  Sunday?
11. 这所学校就是你们上个礼拜参观过的那所吗？
Is this school the one that you visited last  Sunday?
12. 他们曾经居住过的是在这个地方里。
It is in this place that he once lived.
13. 这是他们曾经住过的地址。
It  is the place where he once lived.
14. 他有两个儿子，每一位都看起来像他。
He has two sons, either of whom looks like him.
15. 他有连个儿子，并且每一个都看起来像他。
He has two sons, and either of them looks like him.
16. 这是一本封面是蓝色的书。
17. This is a book whose cover is blue.=This is a book,of which the cover is blue=This is a book,the cover of which is blue.
18. 他不说令她生气的话。He said nothing that made her angry.
19. 那就是他拒绝在会上发言的理由。That was the reason why/for which he refused to speak at the meeting. =That was the reason which/that he refused to speak for at the meeting.
20. 那就是前几天麦克给我的理由。
That was the reason that/which Mac gave me.
21. 正如我们大家都知道的一样，比尔盖茨创建了微软公司。
As is known to us all, Bill Gates founded Microsoft on his own.
22. 比尔盖茨创建了微软公司是我们大家都知道的。
It is known to us all that Bill Gates founded Microsoft on his own.=That Bill Gates founded his own Microsoft is known to us all.
23. 是他那夹杂着乡村音乐，布鲁斯音乐和福音的风格成就了他的名气。你是同谁一起去看的电影？
It is his voice, with his country, blues and Gospel styles, that made him famous. Who was it that you went to the movie together with?=With whom was it that you went to the movie together..
24. 他不像是那种把工作留下一半的那种人。
He isn’t such a man as would leave his work half done.
25. 我要用与你们工厂里用过相同的那种工具。
I prefer to use the same tools as  were used in your factory.
26. 我丢了一本书，书名我一时记不起来了。
I  have lost a book whose title escapes me at the moment.=I lost a book,of which the title escapes me at the moment. 
27. 像你在读的那本小说我不欣赏。
I don’t enjoy such a book as you are reading.=I don’t appreciate the  same book as you are reading.
28. 擦黑板的那一位应该受到表扬
The one who cleans the blackboard should be praised.。
29. 我在初中度过的那三年我永远不会忘记。
I will never forget the three years that I spent in the junior middle school
30. 那不是我做事情的方法。
That isn’t the way( in which/that)  I do it.
31. 他们能用不同的方法拼写单词，这是你们发现有趣的方法。
They could spell words in different ways which/that you might find interesting.=They could spell words by different means that /which you might find interesting.
32. 照现在的样子抄写这个表达词语，不要有任何更改。
Copy this expression as it is; don’t make any change.
33. 我们将尝试着帮助家长改善他们与孩子交谈的方式。
We will try to help parents improve the ways (that/in which) they talk with their children.
34. 只有用这种方法才会停止比尔盖茨的快速成功。
Only in this way/by this means can Bill Gates’ quick success be stopped.=Only in this way/By this means can they stop Bill Gate‘s quick success。
35. 这位在救援中左脚受伤的士兵，年仅二十岁。、
The soldier whose left foot got wounded during the rescue is only twenty years old.
36. 他们破坏法律的方式开始的时候是和平的。
At first the ways that/in which they broke the laws were peaceful.




PART4: 经典状语从句
1．条件状语从句：
1）Let's go out for a walk unless you are too tired.( 除非,若不；相当于if---not)
即：If you are too tired,we’ll not go out for a walk.
2）You may borrow my book as long as you keep it clean.(只要，表示条件的唯一性)
3）Take your umbrella in case it rains.（以防---，以免---）
4）I can tell you the truth on condition that you promise to keep a secret.(条件是---)
5）Supposing it rains, shall we continue the sports meeting?( 如果,假如)
6）He won't be against us in the meeting provided/providing that we ask for his advice in advance.( 假如,除非以……为条件)
7）You will be successful in the interview once you have confidence.(一旦---就--)


2.时间状语从句：
1）When she came in, I stopped eating. (当---的时候，表示“瞬时动词”)
2）While my wife was reading the newspaper, I was watching TV. (当---的时候，was reading是延续性的动词，was reading和was watching同时发生)
3）I like playing football while you like playing basketball.（然而，表示“对比”）
4）As we was going out, it began to snow.（as强调句中两个动作紧接着先后发生，而不强调开始下雪的特定时间）
5）We always sing as we walk.（as表示“一边……一边”）
6）Einstein almost knocked me down before he saw me.(“在---之前”或“----才”) 
7）My father had left for Canada just before the letter arrived.（“刚好在---之前”或“---就”）
8）After you think it over, please let me know what you decide. （在---之后）
9）I didn't go to bed until（till）my father came back.(“直到----才”，主句中的动词为非延续性动词)
10）I worked until he came back. (“直到----才”，主句中的动词为延续性动词)
11) Where have you been since I last saw you? (自从---)
12) I will go there directly I have finished my breakfast. (一----就---，另外有immediately,  instantly)
13)The moment I heard the news, I hastened to the spot. (一----就---，另外有the instant, the minute，ect.) 
14)As soon as I reach Canada, I will ring you up. (一----就---)
15) He had no sooner arrived home than he was asked to start on another journey. (一----就---,另外有hardly/scarcely----when---)
16) By the time you came back, I had finished this book.(“到---时为止”，从句是一般过去时，主句是过去完成时。)
17)By the time you come here tomorrow, I will have finished this work. (“到---时为止”，从句是一般现在时，主句是将来完成时。)
18) Each time he came to Harbin, he would call on me.( “每当---的时候”或“每次”，复习each time, every time和whenever)


3．有关时间状语从句的重点句型
1）It will be four days before they come back. (It will be--- before---过很久才----)
2）It won’t be four days before they come back.( It won’t be---before---不久就---)
2）It was not until the meeting was over that he began to teach me English.(“ It was not until---that----” not until的强调句型)
3）Not until the meeting was over did he begin to teach me English.( not until的倒装句型。)
4) It is/has been five months since our boss was in Beijing.我们老板离开北京有五个月了。(“It is/has been---since” 自从---以来多长时间)
5) Hardly had I sat down when he stepped in.我刚坐下，他就进来了。（“hardly/scarcely----when---”/同“no sooner ---than” 注意时态的应用。）


4．原因状语从句
1)The sweater shrank because it was washed badly. (强调“直接原因”)
2)Since [As] we’ve no money, we can’t buy it. （由于）
3) Since you are free today, you had better help me with my mathematics. （“既然”强调双方共知的原因,复习 “now (that),seeing (that)， considering (that)， in that”）
4）He could not have seen me, for I was not there.( for引导的原因状语从句并不说明主句行为发生的直接原因， 只提供一些辅助性的补充说明， for引导的原因状语从句只能放于主句之后并且必须用逗号将其与主句隔开。)
5）The country is not strong because it is large. 国强不在大。(“not ... because”结构中的not否定的是because引导的整个从句)


5结果状语从句
1) There is so rapid an increase in population that a food shortage is caused.(太---以至于)
2) They are such fine teachers that we all hold them in great respect. (太---以致于)
3) It was very cold, so that the river froze.（以致于）
4) 注意状语从句与too….to..enough to…, so… as to结构的不同。


6．目的状语从句
1）You must speak louder so that /in order that you can be heard by all.( 为了；以便)
2）He wrote the name down for fear that (生怕，以免)he should forget it.
3）Better take more clothes in case (以免)the weather is cold.
4) Say it louder(so)that everyone can hear you.( 以便)


7．让步状语从句
1）Although/Though he was worn out, (still) he kept on working.( 虽然，纵然,尽管)
2) Object as you may, I’ll go.( 虽然，纵然，尽管)
3)Hard as/ though he works, he makes little progress. ( 虽然，纵然，尽管)
4)Child as/though he was, he knew what was the right thing to do. ( 虽然，纵然，尽管)
5) We’ll make a trip even if/though the weather is bad. (“即使……”)
6) You'll have to attend the ceremony whether you're free or busy. (“不论是否……”，“不管是……还是……”)
7) No matter who you are, you must keep the law.(=Whoever you are, you must keep the law.（无论谁，复习no matter +疑问词引导的状语从句。）
8）While I like the colour, I don't like the shape.（尽管）


8．方式状语从句
1）Just as we sweep our rooms, so we should sweep backward ideas from our minds.
2）They completely ignore these facts as if (as though) they never existed.
3）说明：as if / as though也可以引导一个分词短语、不定式短语或无动词短语，例如：He stared at me as if seeing me for the first time.（他目不转睛地看着我，就像第一次看见我似的。）
He cleared his throat as if to say something.（他清了清嗓子，像要说什么似的。）
The waves dashed on the rocks as if in anger.（波涛冲击着岩石，好像很愤怒。）
4）Please pronounce the word the way I do.(用---方式)
5）Leave the things as they are.(按照---)


9．比较状语从句
1）You seem to know music as well as you know astronomy.(as---as 结构)
2）There was no garden so lovely as his in this city. (no so---as 结构)
3）There were not so many tickets available as were asked for. (not so---as 结构)
4）Finally he has made as much money as he wanted. (as +adj +n.+as 结构)
5）Your watch is not the same as his.(the same as结构)
6）I never met such a man as your younger brother.(such---as 结构)
7）She studies more diligently than her classmates.(more than结构)
8）No other book has had a greater influence on my life.(否定词和比较级连用表示最高级含义。)
9）This teacher explained the problem more clearly than any other teacher. (比较级与 “any other one”连用表示最高级含义。)
10）The more you read, the better will you write.(the more----the more 结构)11) He earned no more than 800 dollars a month. 他一个月只挣800美元。（no +比较级+than结构）.
10．地点状语从句
1)Where there is a will, there is a way.
2)You should have put the book where you found it.
3) Wherever there is smoke , there is fire.
4) When you read the book, you’d better make a mark where you have any questions.
5) You should make it a rule to leave things where you can find them again