语法——Noun clauses as the subject


如果一个句子在复合句中充当一个主语, 那么这个句子就是主语从句。

①That he finished writing the composition in such a short time surprised us all.

②What we need are good doctors.

③Whom we must study for is a question of great importance.


1).连接词: that, whether

①.That he will win is certain.

②.Whether he’ll join us in the discussion is of great importance.

2).连接代词: who, what, which, whom , whose, whoever, whatever, whichever

①.It is clear who is afraid of having a change in land ownership.

②.What India needs is a law to make land ownership fairer.

3).连接副词: when, where, why, how, how many, how much , how long, how soon, how often

①When we’ll start tomorrow will be told soon.

②Where we can buy oxen is something we need to find out.

③Why he came here is not known.

④How we can protect the grain from damp needs to be discussed.


1. that—— 2. whether——3. who ——

4. what——5. which—— 6. when, where ——7. why, how—— 8. whoever、whatever、whichever可引导主语从句。


1. 引导主语从句连词有that, whether, who, what, whatever等。

2. 连词位于句首不能省略。

3. 主语从句大多数情况下视为第三人称单数, 但在连接代词what引导的主语从句后谓语动词的数要根据句意而定。

★为了防止句子头重脚轻,通常把形式主语it 放在主语位置,真正主语后置。

1. It is certain 2. It is true 3. It is very likely 4. It is strange 5. It is a pity6. It is still a mystery

7. It is said 8. It seems【小结】

1.以that 引出的主语从句,常以形式主语it引导, 结构为:It is +形容词/名词/某些动词ed + that 从句。

2.在有些that从句中要用虚拟语气 (should +do/should +have done)。

★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 + 不及物动词 + 从句

It seems that? 似乎?

It happened that? 碰巧?

It appears that? 似乎?

(4) It +be+ 过去分词 + 从句

It is reported that? 据报道?

It has been proved that?已证实?

It is said that? 据说?

★“It” 作形式主语代替主语从句的常见句型举例

①It’s + adj. + that / wh- clause

e.g. It’s clear / natural / certain that clause

It’s obvious that money doesn’t grow on trees.

②It’s + p.p. + that / wh- clause

e.g. It’s said / reported / known that clause

It’s believed that he will come next week.

③It ‘s + n. + that / wh- clause e.g. It’s a shame / an honour / good news that clause

It’s still a question when we’ll have our meeting.

④It + v. (n. / pron.) that /wh- clause

e.g. It made us very happy that she was chosen. It appears that he forgot to sign the letter.

★whether与if均为“是否”,但下列情况下只用whether :

1. 引导主语从句并在句首 ——

2. 引导表语从句 ——The question is 3. whether从句作介词宾语 ——I’m not sure about 4. 引导让步状语从句时 ——’ll have to do it.


1. 主语从句位于句首时必须由连接词引导。

2. 主语从句后置时引导词that可省略。

3. 主语从句位于句首时,不能用if 引导。

4. 主语从句后置时, 可以用if引导。


1. makes this shop different is that it offers more personal services.

2. These wild flowers are so special I would do I can to save them.

3. in the regulations that you should not tell people the passport of your e-mail account.

4. It is pretty well understood

5. made the school proud wasmore than 90% of the students had been admitted to key universities.

6. It now appears they are in need of help.


8. It is good news they will arrive in a few days.

Use the words below to fill in the blanks

1. ______ watch was lost is unknown.

2. ________ you did is right.

3. _________ we will go for an outing tomorrow remains unknown.

4. ______ we need is time.

5. ______ will be our monitor hasn't been decided yet.

whether what who whose whatever









1. Whose watch was lost is unknown.

2. Whatever you did is right.

3. Whether we will go for an outing

tomorrow remains unknown.

4. What we need is time.

5. Who will be our monitor hasn't been

decided yet.

1. Whose watch was lost is unknown.

2. Whatever you did is right.

3. Whether we will go for an outing

tomorrow remains unknown.

4. What we need is time.

5. Who will be our monitor hasn't been decided yet.

2. 在有些that从句中要用虚拟语气

(should +do/should +have done)。


2. 谁会赢得比赛还不知道。

3. 谁来都欢迎。

4. 那个人为什么被谋杀尚不知道。

Where he was born has not been found.

Why the person was murdered is still unknown.

Who will win the match is still unknown.

Whoever comes is welcome.

5. What the teacher said today was quite right.


6. That they are badly in need of help is quite clear.


7. Whether they will sell the house is not yet decided.


8. Whatever was said here must be kept secret.


9. Whoever makes mistakes must correct them.


10. It is a pity that she has made such a mistake.

她犯了这样一个错误, 真是遗憾。

11. It is believed that at least a score of buildings were damaged or destroyed.

据信, 至少有二十座楼房遭到破坏或彻底毁掉。

12. That they were true sisters was clear from the facial resemblance between them.


13. Whether he’ll come here isn’t clear.


14. What she did is not yet known.


15. 无论他说什么都不重要。

Whatever he says is of no importance

16. 无论谁说这话都不对。

Whoever says that is wrong.

17. How this happened is not clear to anyone.


18. Whoever comes is welcome.


19. 不管是谁犯了法,他都应该受到惩罚。

Whoever breaks the law should be punished。

1. _____ you don’t like him is none of my business.

2. _____ he said at the meeting astonished everybody present.

3. ________ the 2000 Olympic Games will be held in Beijing is not known yet.

4. ________ we’ll go camping tomorrow depends on the weather.

5. ________ leaves the room last ought to turn off the lights.







6. ___ is a fact that English is being accepted as an international language.

7.It worried her a bit ____ her hair was turning grey.

8. The Foreign Minister said, “__ is our hope that the two sides will work towards peace.”

9. After Yang Liwei succeeded in circling the earth, ____ our astronauts desire to do is walk in space. It








(1) 由连词that引导的主语从句:引导词that无含义/在句中不做成分/不可以省。 例如:That you will win the medal seems unlikely.

That you are so indifferent bothers me.

That she survived the accident is a miracle.

(2) 用连词 whether 引导的主语从句: whether有含义(是否)/在句中不做成分/不可以省。


例如:Whether we will hold a party in the open air tomorrow depends on the


Whether she is coming or not doesn’t matter too much.

(3) 用连接代词引导的主语从句

在由连接代词who, whose, whom, which, what, whoever, whomever, whichever, whatever引导的名词性从句中,


例如:What you need is more practice.

What I want to know is this.

Whatever we do is to serve the people.

注:whatever / whoever的功用

whatever, whoever在主语从句中不含疑问意义。它引导主语从句,并在从句中作主语、宾语、表语等。

whatever = anything that; whoever = anyone who。要注意和whatever, whoever引导的让步状语从句的区别。


Whoever breaks the law should be punished. (主语从句)

( =Anyone who breaks the law should be punished. )

Whoever breaks the law, he should be punished. (让步状语从句)

( =No matter who breaks the law, he should be punished. )

(4)用连接副词when, where, why, how引导的名词性从句(其连接副词有含义,在句中作


例如:Where we should leave it is a problem.

When they will come hasn’t been made pubic.

三.注意点: it构成的主语从句



例如:That light travels in straight lines is known to all.

=It is known to all that light travels in straight lines.

When the plane is to take off has not been announced .

= It has not been announced when the plane is to take off.


错:It is a book what he wants.

对:What he wants is a book.


It was reported that the US was under the terrorist attack.

As was reported, the US was under the terrorist attack.


<a> It is +名词+从句

It is a fact that? 事实是??

It is good news that ? ??是好消息

It is a question that ? ??是个问题

It is common knowledge that ? ??是常识

类似的名词还有:a pity;a wonder;a good thing; no wonder; surprise等。 例如:It is a mystery to me how it all happened.

It is common knowledge that the whale is not a fish.

It is no surprise that Bob should have won the game.

It’s a pity that you missed the film.

<b> It is +形容词+从句

It is necessary that ? 有必要??

It is clear that ? 很清楚??

It is likely that ? 很可能??

It is important that ? 重要的是??

类似的形容词还有:strange; natural; obvious; true; good; wonderful; possible; unlikely; quite;

unusual; certain; evident; worth-while; surprising; interesting; astonishing, etc. 例如:It is doubtful whether she(转 载自:wWw.HN1c.cOM 唯才 教 育网:高中英语主语从句ppt) will be able to come.

It was really astonishing that he refused to talk to you.

It is essential that he should be here by the weekend.

It seems obvious that we can not go on like this.

It is necessary that you (should)master the computer.

It is important that a student learn English well.

It’s clear that they badly need help.

It is likely that a hurricane will arrive soon.


<c> It is +过去分词+从句

It is said that ? 据说??

It is reported that ? 据报道??

It has been proved that ? 已证明??

It must be proved that? 必须指出??

类似的过去分词还有:known; estimated; expected; believed; thought; hoped; noted; discussed; required;

decided; suggested; demanded; made clear; found out,etc.

例如:It is thought that he is the best player.

It is estimated that the vase is 2000 years old.

It is used to be thought that a new star must be due to a collision between two stars.

It has not been made clear when the new road is to be opened to traffic.

It is said that he was killed in the earthquake.

<d> It seems (happened / appears / doesn’t matter / makes no difference /

occurred ?)that ?


It seems that they will win the game.

It makes no difference whether he will attend the meeting or not.

It does not matter if I missed my train.

It happened that I saw him yesterday.




从属连词: that, whether;

连接代词: who (whoever), whom, whose, what (whatever)和which (whichever);

连接副词: when, where, how和why。


1. 从属连词:that, whether


2)whether意为“是否”,放在句首句末皆可。由whether引导的名词从句做 主语,表语,介词宾语,同位语时!不可用if代替。

a.That price will go up is certain.

b. Whether they would support us was a problem. 他们是否会支持我们还是一个问题。

2. 连接代词who ,what ,which, whatever, whichever, whoever (Who, whom, which, what可以和ever构成合成词,和what一样引导从句,ever起到强调作用。此类主语从句不能用形式主语it引导,它们在句子中担任成分,不能省略,语序为陈述语序,既有疑问含义,又起连接作用,同时在从句中充当各种成分。

Which side will win is not clear. Whoever breaks the law will be punished.

Whatever he did is right. Who killed the scientist remains a question.

1)What和that引导的主语从句的区别:that 只起引导作用,不充当任何成分,没有意思。What 不仅起引导作用,还要充当一定成分(主语、宾语或表语),意思是:“什么”。

What we need is money. That he will come is certain.

2)whatever / whoever的用法(~ever=no matter ~---让步状语从句中)

whatever / whoever可以引导主语从句,并在句中作主语、宾语、表语等,不含疑问意义。whatever相当于anything that; whoever 相当于anyone who。例如:

Whoever(Anyone who) wants to enter into this school must take the exam.

Whatever(Anything that) she did was right.

3. 连接副词when,where, how,why等。既有疑问含义,又起连接作用,同时在从句中充当各种成分。How this happened is not clear to anyone. When he will be back depends on the weather.When we’ll start tomorrow will be told soon. Where the test will be given is not yet decided.

4. 主语从句后置:为了避免主语冗长,句子头重脚轻,经常用 it 作形式主语,主语从句放在后面作真正的主语.例: That we shall be late is certain. -- It’s certain that we shall be late.

1)用it 作形式主语的结构

A.It + be + 形容词 + that 从句

(obvious, true, surprising, good, wonderful, funny, possible, likely, certain, probable, etc.) 如: It is certain that she will do well in her exam.

B.It + be + 名词词组 + that 从句 (an honour, a fact, a pity, etc)如:

It is a pity/shame that... 遗憾的是…… It is a surprise that…令人惊奇的是…

It is a fact that… …是事实 It is common knowledge that… …是常识

It’s a pity that we can’t go.

C.It + be + 过去分词 + that 从句 (said, reported, thought, expected, decided, announced, etc。) 如: It is said that Mr. Green has arrived in Beijing.

D.It + 不及物动词或短语 + that 从句 ( seem,happen, doesn’t matter ,turn out) 。如:It happened that I was out that day. It doesn’t matter whether she will come or not.

2) 对于以连接代词(副词)引导的主语从句,可以使用形式主语代主语从句,也可直接在句首使用主语从


a. Whether they would support us was a problem. b. It was a problem whether they would support us.



It doesn’t seem that they are from the same university.

It doesn’t appear that we’ll have a sunny day tomorrow.

5. 注意:


误:They should like each other is natural. 正: That they should like each other is natural.

2)在 It + be + suggested/advised/ordered/requested/ insisted/required 中, that从句的谓语也应该用“should + 动词原形”的形式, should有时可以省略。主语从句中用陈述语序,后面的谓语动词用第三人称单数. It is suggested that we (should) do the experiment a second time.

3) . 用于 It is important / natural / necessary / impossible that...句型中, 主语从句应使用虚拟语气, 用“should + 动词原形”的形式, should有时可以省略。

It is important and necessary that we (should) keep the balance of nature.


eg:What you left are only several old books. What you said is of great importance.

5)在It is funny, strange, surprising, a pity, a shame, no wonder, etc. + that从句中,有时谓语部分用should + 动词原形,来表达说话者的感情色彩,此时should也可省略。


"It be + adj./n. + that-clause"与强调句型均有It be...that...之类的语言标志,但不同的是:①前者中的that从句是主语从句.若删掉其中的It be和that,则剩余部分不论结构还是语意都不能成为一个句子;但若将后者中的It be和that去掉,则剩余部分的结构和语意仍能构成一个完整的句子.②强调句型译为汉语时可加上"正是……"或"就是……"之类的字眼,而主语从句则不可以.

It is surprising that Mary should have won first place.令人惊奇的是玛莉竟然获得了第一名.

It is Mary that has won first place.正是玛莉得了第一名.【强调】


例1.When will he come is not known. 正:When he will come is not known.


例2. He will not come to the meeting this evening is true.

正:That he will not come to the meeting this evening is true.

规律二、连词that 在从句中无实际意义,但不能省略。

例3. If the meeting will be put off has not been decided yet.

正: Whether the meeting will be put off has not been decided yet.

规律三、whether 可以引导主语从句,放在句首,但if不能

例4. That whether he will help others is a fact.

正:That he will help others is a fact.


例5. When he will come are a puzzle. 正:When he will come is a puzzle.


1. What he needs is that book.2. What he needs are some books.

规律六、what 引导的主语从句,可根据表语决定主句动词的单复数形式。

规律七、主语从句为了避免头重脚轻现象,用 it 做形式主语,而把从句放在后面。

That the earth turns around the sun is known to all.

It is known to all that the earth turns around the sun.

1.what / that

a.____ he said at the meeting surprised us. b._____ he turned up at the meeting surprised us.

2. if / whether _______you go or stay at home won’t make any differences.

3.it What a pity _____is _____you didn’t arrive by daylight.

A. there, because B. it, that C. he, whenD. that, for

4.no matter how/who/what/where/when

We are ready to do ______ the country wants us to do.

A. whatB. which C. no matter whatD. whatever

5.It is a pity that you (should) miss such a good chance.

___ he made an important speech at the meeting was true.

A. That B. Why C. What D.How

6. ___we’ll go camping tomorrow depends on the weather .

A If B Whether C That D Where

7.___ is known to us all is that America is a developed country .

A Which B AsC WhatD It

8. It’s known to us all ___ a form of energy .

A. water is B. that water isC. is water D. that water to

9. It worried her a bit ___ her hair was turning gray.

A. whetherB. that C. what D. when

10.What I say and think ___ none of your business.

A. is B. are C. has D have

11. ____ his dream of going to college will come true is uncertain.

ThatB. Whether C. IfD. Even if

12. It is known to us ___ where there is pollution, there is harm.

A. which B. whereC. what D. that

13. --- I saw your neighbor break your window with a basketball.

--- ____ it made me nearly mad.

A. That he broke B. What he brokeC. He brokeD. His break

14.It remains a question ____ we can get so much money in such a short time.

A.how B. thatC. when D. what

15. He made a promise ___ anyone set him free he would make him very rich.

A. thatB. if C. what D. that if

16. They lost their way in the forest and ____ made matters worse was ___ night began to fall.

A. what; that B. it; that

C. what; whenD. which; what

17. ________that they found an unusual plant in the forest.

A. It is said B. They are said C. It said D. It says

18. _____ caused the accident is still a complete mystery.

A. What B. That C. How D. Where

19. It worried Mary a lot _____ she would pass the college entrance examination.

A. whether B. if C. that D. how

20. ____ is no possibility ______ Bob will win the first prize in the match.

A. There, that B. It, that C. There, whether D. It, whether

21. ____surprised me most was _____such a little girl of seven could play the violin so well.

A. That; what B. What; that C. That; that D. What; what

22. _____ helped to save the drowning girl is worth praising.

A. Who B. Anyone C. Whoever D. The person

23. ____ she couldn’t understand was _____ fewer and fewer students showed interest in her lessons.

A. What; why B. That; why C. What; because D. Why; that

24. It was ____ he said ___ disappointed me.

A. What; that B. That; that C. What; what D. That;what

25. ___ is a fact that English is being accepted as an international language.

A. There B. This C. That D. It

26. ______leaves the room last ought to turn off the lights.

A. Anyone B. The person C. Whoever D. Who

27.________ makes mistakes must correct them.A. What B. That C. Whoever D. Whatever

28. Is this factory you visited the other day?

A. that B. where C. in which D. the one

29.When and why he came here ________ yet.

A. is not known B. are not known C. has not known D. have not known

30. ________ is no reason for dismissing her.

A. Because she was a few minutes late B. Owing to a few minutes late

C. The fact that she was a few minutes late D. Being a few minutes late

31. ________ Tom liked to eat was different from ________.

A. That…that you had expected B. What …that you had expected

C. That…what you had expected D. What…what you had expected

32.________ we go swimming every day ________ us a lot of good.

A. If...do B. That...do C. If...does D. That...does

33.It ________ Bob drives badly.

A. thinks that B. is thought what C. thought that D. is thought that

34.It's uncertain ________ the experiment is worth doing.

A. if B. that C. whether D. how

35.________ the boy didn't take medicine made his mother angry.

A. That B. What C. How D. Which

36.____ we can't get seems better than ____ we have.

A. What, what B. What, that C. That, that D. That, what

37.____ you don't like him is none of my business.

A. What B. Who C. That D. Whether

38..____ we'll go camping tomorrow depends on the weather.

A. If B. Whether C. That D. Where

39._________is going to do the job will be decided by the Party committee.

A. That B. Why C. How D. Who

40._______we'll finish translating the book depends on the time.A. When B. Why C. What D. That

41.______he won't go there is clear to all of us.A. How B. What C. Why D. This

42.______the house will be built will be discussed at tomorrow's meeting.

A. If B. Where C. That D. What

43_______you come or not is up to you. A. What B. If C. Why D. Whether

44._______team will win the match is a matter of public concern. A. Which B. That C. If D. How

45 Is this the factory ___ some foreign friends visited other day?

A that B where C which D the one

46 Is this the factory ___ he worked ten years ago?

A that B where C which D the one

1. what / that 2. Whether3--10 BDA BCBBA 11--20 BDAAD AAAAA21--30 BCAAD CCACC31--40 DDDCA ACBDA41--46 CBDAAB