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名词性从句
在句子中起名词作用的句子叫名词性从句(Noun Clauses）。 名词性从句的功能相当于名词词组, 它在复合句中能担任主语、宾语、表语、同位语、介词宾语等，因此根据它在句中不同的语法功能，名词从句又可分别称为主语从句、宾语从句、表语从句和同位语从句。
第一节 知识点讲解
顾名思义，主语从句在句子中作主语。有时本身出现在主语的位置上，也有时出于句子结构的考虑退到句子的尾部，前面用形式主语it代替。从句作主语时，谓语动词一般为单数形式。如:
Tips: 主语从句的that绝对不能省去。因为句子是不能做主语的，故用that引导。若去掉则没有了主语，而宾语从句的that可省。
主语从句：That he is right is known to all of us.
宾语从句：We all know (that) he is right.
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。被强调部分指人时也可用who/whom。例如： a) It is a pity that you didn’t go to see the film. 你不去看那场电影真可惜。
b) It doesn’t interest me whether you succeed or not. 我对你成功与否不感兴趣。
c) It is in the morning that the murder took place. 谋杀案是在早上发生的。（强调句型）
d) It is John that broke the window. 是John打碎的窗户。（强调句型）
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…
It appears that… 似乎…
(4) It ＋ 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…
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：
正确表达：It is said that President Jiang will visit our school next week.
错误表达：That President Jiang will visit our school next week is said.
（3）It happens/occurs…结构中的主语从句不可提前。例如：
正确表达：It occurred to him that he failed in the examination.
错误表达：That he failed in the examination occurred to him.
（4）It doesn’t matter how/whether …结构中的主语从句不可提前。例如：
正确表达：It doesn’t matter whether he is wrong or not.
错误表达：Whether he is wrong or not doesn’t matter.
（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：
正确表达：Is it likely that it will rain in the evening?
错误表达：Is that will rain in the evening likely?
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 则不然。例如：
a) What you said yesterday is right.
b) That she is still alive is a consolation
宾语从句就是在复合句中作宾语的名词性从句，通常放在主句谓语动词 (及物动词) 或介词之后。
1. 作动词的宾语
(1) 由that引导的宾语从句(that 通常可以省略), 例如：
I heard that be joined the army. 我听说他参军了。
(2) 由what, whether (if) 引导的宾语从句，例如：
a) She did not know what had happened. 她不知道发生了什么。
b) I wonder whether you can change this note for me. 我想知道你是否能帮我改一下笔记。
(3) 动词＋间接宾语＋宾语从句。例如：
She told她对我说她会接受我的邀请。
2. 作介词的宾语，例如：
Our success depends upon how well we can cooperate with one another. 我们的成功取决于我们之间的合作。
3. 作形容词的宾语，例如：
I am afraid (that) I’ve made a mistake. 我恐怕我已经犯了一个错误。
注意：that 引导的从句常跟在下列形容词后作宾语：anxious, aware, certain, confident, convinced, determined, glad, proud, surprised, worried, sorry, thankful, ashamed, disappointed, annoyed, pleased, hurt, satisfied, content 等。也可以将此类词后的that 从句的看作原因状语从句。
4. it 可以作为形式宾语
it 不仅可以作为形式主语，还可以作为形式宾语而真正的宾语that 从句则放在句尾，特别是在带复合宾语的句子中。 例如：
We heard it that she would get married next month. 我听说她下个朋就会结婚了。
5. 后边不能直接跟that 从句的动词
这类动词有allow, refuse, let, like, cause, force, admire, condemn, celebrate, dislike, love, help, take, forgive等。这类词后可以用不定式或动名词作宾语，但不可以用that引导的宾语从句。如：
正确表达：I admire their winning the match.
错误表达：I admire that they won the match.
6. 不可用that从句作直接宾语的动词
有些动词不可用于“动词＋间接宾语＋that从句“结构中，常见的有envy, order(命令), accuse, refuse, impress, forgive, blame, denounce（公开指责）, advise, congratulate等。例如：
正确表达：He impressed the manager as an honest man.
错误表达：He impressed the manager that he was an honest man.
7. 否定的转移
若主句谓语动词为think, consider, suppose, believe, expect, fancy（想象）, guess, imagine等，其后的宾语从句若含有否定意义，一般要把否定词转移到主句谓语上，从句谓语用肯定式。例如：
I don’t think this dress fits you well. 我认为这件衣服不适合你穿。
三．【表语从句】
表语从句在复合句中作表语的名词性从句，放在系动词之后，一般结构是“主语＋连系动词＋表语从句”。可以接表语从句的连系动词有be, look, remain（留下、保持、依然）, seem等。引导表语从句的that常可省略。另外，常用的还有the reason is that… 和It is because 等结构。例如：
1) The question is whether we can make good preparation in such a short time.
2) This is why we can’t get the support of the people.
3) But the fact remains that we are behind the other classes.
4) The reason he is late for school is that he missed the early bus.
同位语从句就是在复合句中作名词的同位语的名词性从句。
1. 同位语从句的功能
同位语从句对于名词进一步解释，说明名词的具体内容，一般由that引导，例如：
1) The king’s decision that the prisoner would be set free surprised all the people.
2) The order that all the soldiers should stay still is given by the general.
2. 同位语在句子中的位置
同位语从句有时可以不紧跟在它所说明的名词后面，而是被别的词隔开。例如：
He got the news from Mary that the sports meeting was put off.
3. 同位语从句与定语从句的区别
（1）. 同位语从句和定语从句相似，二者都有先行词。同位语从句是对先行词的进一步陈述，和先行词是同等的关系，含义相同。定语从句是对先行词的修饰或限制。
（2）. 同位语从句表示先行词的内容是什么，进一步说明先行词。定语从句与先行词之间是所属关系，表示“ …的 ” ，起修饰作用。
（3）. 同位语从句的“ that ” 不能省略。定语从句的关系代词“ that ” 在从句中作宾语时可以省略。
（4） 同位语从句的先行词是一个含有概念的抽象名词，从句对这一概念进行展开或说明。
1.正确使用同位语从句的关连词； 2.正确运用同位语从句的先行词； 3.能正确认识并正确翻译同位语从句。 同位语从句和定语从句比较练习
1. I heard about the news that he got a full mark in this examination.（同位语从句）
2. This is good news that I heard from Mary. （定语从句）
3. He can’t answer the question how he got the money. （同位语从句）
4. This is an easy question that he answered in class. （定语从句）
通过以上介绍，我们可以看出，四种名词性从句都需要有一个连接性词在从句的开头。这个词是什么性质，要看它在从句中作作的成分，如果作的是主语、宾语、表语的话，这个词就是连接代词；如果作的是各种状语，就叫连接副词；如果不作任何成分，就叫连接词。
引导名词性从句的连接词 ：
连接词 that, if, whether
连接代词： who, whom, what, whose, which, whichever, whatever, whoever
连接副词 when, where, how, why
第二节 考点分类解析
【考点一：语序问题】
名词性从句的语序：永远陈述语气。即名词性从句中不会出现助动词提前的现象。如：
Who he is doesn’t matter much.
When and where we shall have the sports meet is a question.
I don’t know what his name is.
I don’t know what is wrong with him. = I don’t know what is the matter with him.
You can’t imagine how excited I was at that time.
Can you tell me what size shoes you wear?
No one can be sure ______ in a million years. （MET1991）
A. what will man look like
C. man will look like what B. what man will look like D. what look will man like
【考点二：that和what的区别问题】
能引导名词性从句的关系代词有who, whom, what, whose, which, whichever, whatever, whoever八个。为何单独讲what的用法呢？重要！在考试中出现的频率高！在本书第一章《定语从句》中，我们提到过，what是不能引导定语从句的。定语从句中如果缺少的成分是主语、宾语、表语，我们选择的是关系代词that或其他。现在山头换了，到了名词性从句的知识范围了。What在名词性从句中就很有用武之地了。还是分析成分，what 在从句中作的主语、宾语、表语。而that只是一个“连接词”，既不作什么成分，也没有什么意义。如:
What you did doesn’t agree with what you promised.
What he couldn’t understand was why his teacher was never satisfied with him.
The matter of salary is what I care most if I decide to change my profession.
What we can’t get always seems better than what we have already got.
I think that your composition is no better than his.
That you don’t love her is not my business.
What we have seen is different from _______.
A. we heard B. we have heard C. what we heard D. what we have heard
答案：D。我们应该可以看出这是个宾语从句。从句中hear是个及物动词，缺少宾语。所以，应该选有what引导的从句。而不能是that或者省略了that的情况。
I couldn’t agree with ______ at the meeting.
A. that you said B. which you said C. all what you said D. what you said
答案：Ｄ。与上一题相同，这也是一个考查宾语从句的题目。从句中的say是个及物动词，缺少宾语。所以，应该选择what引导的宾语从句。但是，这个题目最容易错的选项是Ｃ。 因为有些同学会认为all是先行词，而后面时what引导的定语从句。但是，what是不引导定语从句的。所以，Ｃ根本就是不存在的。
【考点三：that和whether的区别问题】
有时候，它们两个比较难以区别，因为，它们都是连接词，都在从句中不作成分。但是，它们之间最大的区别在于“意义”。即that在从句中既不作成分，也没有自己的意义；而whether就不同了。它虽然不在从句中作什么成分，但是它又意义，即“是否”。这就能够左右从句的意思，使从句所表达的意思变成一个还没有确定的因素。如：
I don’t know whether he can join us or not.
I’m sure that he can join us.
It is none of your business whether I love her.
It is none of your business that I don’t love her.
综上所述，区分that还是whether，重要一点就是看主句需要从句表达一个什么意思，是确定的，还是不确定的；是事实还是疑问。前者选that，后者选whether。如：
I have no doubt _____ Mr. Johnson will make it here on time.
A. that B. whether C. why D. when
No one can be sure _____ the board will accept our conditions.【高中英语名词性从句】
A. that B. whether C. why D. what
【考点四：if和whether的区别问题】
二者在引导宾语从句时都有“是否”之意。但并不是永远可以互换。一般认为，二者可以互换的环境也只有在宾语从句中。如：
He didn’t give us explicit reply whether/if he will attend our wedding ceremony.
名词性从句练习100题
1. Nowadays consumers become more and more practical and buy only _______ they need.
A. where B. which C. when D. what
2. She’d like to offer money to ________ needs it to continue his or her study.
A. who B. whom C. whoever D. whomever
3. ---If you are admitted to a key university, _________ as a prize?
--- I’m looking for a cell phone.
A. What you expect your father will offer you
B. Do you expect what your father will offer you
C. What do you expect will your father offer you
D. What do you expect your father will offer you
4. Yesterday he sold out all his stamps at ____ he thought was a reasonable price.
A. that B. which C. what D. as
5. Generally speaking, ____ we have seen seems more believable than ____ we have been told.
A. what; that B. what; what C. that; what D. that; that
6. After three days’ waiting, there was a little doubt in the mother’s mind _______ the police could find her lost child.
A. how B. that C. where D. whether
7. ―Sustainable development‖ is a question _______ we can continue developing the world without damaging the environment.
A. why B. when C. that D. how【高中英语名词性从句】
8. We’d like to do _______ we can _________ the poor.
A. how; help B. all; to help
C. whatever; help D. however; to help
9. My parents used ________they had to get a new car for my brother.
A. which B. all what C. what D. 不填
10. She was so angry at all ________ he was doing _________ she stayed up all night.
A. that; that B. that; which C. what; that D. what; as
11. After _________ seemed ages, the newsman disclosed the facts.
A. there B. which C. what D. that
12. Our school is no longer _________ it was 10 years ago, _________ it was not well equipped.
A. what; which B. that; which C. what; when D. that; where
13. Our bad living habits will destroy the earth. Only by changing ________we live can we save the earth.
A. that B. what C. how D. where
14. Thinking that you know _________ in fact you don’t is a serious mistake
A. what B. that C. when D. however
15. Energy is _________ makes things work.
A. what B. everything C. something D. anything
16. One of the men held the view __________the book said was right.
A. that what B. what that C. that D. whether
17. I think that this meal was well worth ________ was charged for it.
A. that B. what C. which D. how many
18. Do you think the reason ________ he gave is believable?
A. for which B. which C. why D. what
19. Although he knew little about the large amount of work done in the field, he succeeded ________ other more well-informed experimenters failed.
A. which B. that C. what D. where
20. Although Anne is happy with her success she wonders________ will happen to her private life.
A. it B. that C. what D. this
21. The news has spread all over the country ________ the spaceship succeeded in returning to the earth.
A. that B. which C. whether D. what
22. You can choose ________ book you like among these.
A. no matter what B. whatever C. whose D. whichever
23. Is this research center ________ we visited the modern equipment last year?
A. where B. that C. the one D. which
24. Loulan city is not at all _______a traveler who has never seen the desert before can expect.
A. what B. that C .which D. where
25. What the doctor is uncertain about is ______ my mother will recover from the serious disease soon.
A. when B. how C. whether D. why
26. We should buy our daughter a computer in ______ it can help to improve her English.
A. which B. that C. what D. whom
27. I wish to have a friend with ______ shares my hobbies and interests.
A. whomever B. no matter who C. whoever D. anyone
28. Why don’t you bring _______ to his attention that you are too busy to do it.
A. this B. what C. that D. it
29. The task required _______ did it ______ careful and brave enough.
A. who; is B. whom; was
C. whomever; were D. whoever; be
30. We wrote a letter of thanks to _______ had helped us.
A. who B. those C. whom D. whoever
31.--- What are you anxious about?
--- ___________.
A. Whether we can succeed B. If we succeed
C. Do you succeed D. That we can succeed
32. I just don’t understand_______ that prevents so many Americans from being as happy as one might expect.
A .why it does B. what it does C. what it is D. why it is
33. ---I rang you at about ten, but there was no reply.
---Oh, that was probably _________ I was seeing the doctor.
A. when B. why C. what D. that
34. I kept this picture ________ I can see it every day as it reminds me of my university days.
A. in which B. where C. when D. whether
35. ---I can’t find Mr. Smith .Where did you last see him this morning?
---It was in the hotel _______ he stayed.
A. that B. where C. which D. since
36. You should keep those old jam bottles ----you never know ______ you might need them.
A. when B. how. C. what D .where
37. ---Do you have anything in mind ______you’d like for supper ?
---Well, ______will do for me.
A. which, everything B. that, anything
C. what, whatever D. that, either
38. After five hours’ drive, they reached _____ they thought was the place they’d been dreaming of .
A. that B. what C. which D. where
39. It is recommended that the project ___ until all the preparations have been made. is not started B. not be started
C. will not be started D. is not to be started
40.______ has finished the work ahead of time will be rewarded though we don't know who it will be.
A. Those who B. Anyone C. Whoever D. No matter who
41. ______ makes the school famous is ______ more than 90% of the students have been admitted to universities.
A. What; because B. That; because
C. That; what D. What; that
42. Everything depends on _____ they will support you about it.
A. if B. which C. whether D. that
43. After ten years, she changed a lot and looked different from___ she used to be.
A. that B. whom C. what D. who
44. I know nothing about the young lady--- ______ she is from Being.
A. except B. except for C. except that D. besides
45. The question came up at the meeting _____we had enough money for our research.
A. that B. what C. which D. whether
46. __________ a terrible storm would take place in Hainan.
A. Word came which B. Word came that
C. Word that came D. Words came that
47. _________ David says sounds right to Helen. That’s why she has made up her mind not to leave him________ happens.
A. whatever; whatever B. No matter what; whatever
C. No matter what; no matter what D. Whatever; however
48. Mr. Hopkins has not yet answered my question________ I can go with him to ________ he calls the Underground Treasure House next week.
A. that; which B. that; where C. whether; that D. whether; what
49. --- Don’t you believe me?
--- ________, I will believe _________ you say.
A. No; whatever B. Yes; no matter what
C. No; no matter what D. Yes; whatever
50. __________ is mentioned above, the number of the students in senior high school is increasing.
A. Which B. As C. That D. It
51. See the flags on top of the building? That was ______ we did this morning.
A. when B. which C. where D. what
52. ―What did your parents think about your decision?‖ ―They always let me do ______ I think I should.‖
A. when B. that C. how D. what
53. ―Could you do me a favor?‖ ―It depends on ____ it is.‖
A. which B. whichever C. what D. whatever
54. There is much chance ____ Bill will recover from his injury in time for the race.
A. that B. which C. until D. if
55. ______ makes this shop different is that it offers more personal services.
A. What B. Who C. Whatever D. Whoever
56. Mary wrote an article on _______ the team had failed to win the game.
A. why B. what C. who D. that
57. The poor young man is ready to accept _______ help he can get.
A. whichever B. however C. whatever D. whenever
58. As soon as he comes back, I’ll tell him when ______and see him.
A. you will come B. will you come
C. you come D. do you come
59. ______ in the regulations that you should not tell other people the password of your e-mail account.
A. What is required B. What requires
C. It is required D. It requires
60. Elephants have their own way to tell the shape of an object and _______ it is rough or smooth.
A. 不填 B. whether C. how D. what
61. The way he did it was different _______ we were used to.
A. in which B. in what C. from what D. from which
62. Great changes have taken place in that school. It is no longer ____ it was 20 years ago, ______ it was so poorly equipped.
A. what; when B. that; which C. what; which D. which; that
63. Danby left word with my secretary ________ he would call again in the afternoon.
A. who B. that C. as D. which
64. ―Don’t you think it necessary that he _______ to Miami but to New York?‖ ―I agree, but the problem is ________ he has refused to.‖
A. will not be sent; that B. not be sent; that
C. should not be sent; what D. should not send; what
65. Some researchers believe that there is no doubt ________ a care for AIDS will be found.
A. which B. that C. what D. whether
66. The old lady’s hand shook frequently. She explained to her doctor ________ this shaking had begun half a year before, and ______, only because of this, she had been forced to give up her job.
A. when; how B. how; when C. how; how D. why; why
67. Do you have any idea _______ is actually gong on in the classroom?
A. that B. what C. as D. which
68. I want to know ________ the thief was caught on the spot.
A. which B. that C. what D. whether
69. Our club is open to adults only. _______ your children have entered without permission.
A. There seems that B. It seems to be
C. There seems to be D. It seems that
70. You are saying that everyone should be equal, and this is ________ I disagree.
A. why B. where C. what D. how
71. The road is covered with snow. I can’t understand _______ they insist on going by motorbike.
A. why B. whether C. when D. how
72. We cannot figure out _______ quite a number of insects, birds, and animals are dying out.
A. that B. as C. why D. when
73. The Foreign Minister said, ―_______ our hope that the two sides will work towards peace.‖
A. This is B. There is C. That is D. It is
74. A story goes _______ Elizabeth 1 of England liked nothing more than being surrounded by clever and qualified noblemen at court.
A. when B. where C. what D. that
75. I have always been honest and straightforward, and it doesn’t matter ____ I’m talking to.
A. who is it B. who it is C. it is who D. it is whom
76. The other day, my brother drove his car down the street at ________ I thought was a dangerous speed.
A. as B. which C. what D. that
77. After Yang Liwei succeeded in circling the earth, ______ our astronauts desire to do is walk in space.
A. where B. what C. that D. how
78. Along with the letter was his promise _______ he would visit me this coming Christmas.
英语名词性从句知识点复习
一、概述
在复合句中具有名词的性质的作主语、表语、同位语、宾语的从句叫名词性从句。因此，我们把主语从句、表语从句、同位语从句和宾语从句这四种从句统称为名词性从句。
It is a fact that English is being accepted as an international language.
事实上英语作为国际语言正为世人所接受。(主语从句)
The trouble is that she has lost his address. 麻烦的是她把他的地址搞丢了。（表语从句） They have no idea at all where he has gone. 他们不知道他去什么地方了。（同位语从句） Do you remember how he came? 你记得他怎么来的么？（宾语从句）
二、语序
名词性从句要采用陈述句语序。由一个含疑问意义的连词引起时，必须将该连词放在名词性从句的开头，且该从句语序不能倒装。
What we can't get seems better than what we have. 我们得不到的似乎比我们所拥有的要好。 The photographs will show you what our village looks like. 这些照片将向你展示我们村庄的面貌。 Can you make sure where Alice has put the gold ring? 你能肯定爱丽丝放金戒指的地方吗？ No one can be sure what man will look like in a million years.
没有人肯定一百万年后人类会是什么样子。
He asked how much I paid for the violin. 他问我花了多少钱买这个小提琴。
三、 时态的呼应
名词性从句特别是宾语从句中谓语动词的时态要与主句中谓语动词时态要相呼应，主要有下列几种情况：
（1）如果主句中的谓语动词是一般现在时态，从句的谓语动词的时态不受主句谓语动词时态的制约。 I wonder why Jenny hasn’t written us recently. We should have heard from her by now. 我不知道为什么珍妮最近没有给我们写信。我们现在应当收到他的来信了。
You haven’t said a word about my new coat, Brenda. Do you like it?
你对我的新装还没说怎么样呢，喜欢吗？
I’m sorry I didn’t say anything about it sooner. I certainly think it’s pretty on you. 对不起，我还没来得及。我认为你穿上当然好看。
（2）如果主句的谓语动词是过去时态，从句的谓语动词动作发生在主句的动作之前，过去完成时、过去完成进行时或一般过去时。
The police found that the house had been broken into and a lot of things stolen. 警察发现有人闯入房子并且很多东西被偷
She said she had been waiting for me for a long time.她说她等了我很长时间。
（3）如果主句的谓语动词是过去时态，从句的动作和主句的动作同时发生，则从句的动词用一般过去时或过去进行时。
I didn’t know you were here.我不知道你在这里。
I was told that they were designing a new machine.有人告诉我他们在设计一种新机器。
（4）如果主句的谓语动词是过去时态，从句的动作发生在主句的动作之后，则从句的动词用过去将来时、过去将来进行时或过去将来完成时。
We were all surprised when he made it clear that he would leave office soon. 当他宣布他不久就要离职时，我们都很吃惊。
They said they would be listening to a report on current affairs.
他说他们将听关于时事的报告。
四、引导名词性从句的关联词
在传统的语法中，有连接代词、连接副词和关系代词、关系副词之分；连接代词、连接副词引导名词性从句和关系代词、关系副词引导定语从句。本书根据最新资料不再作此分类，通称关系代词和关系副词。 引导名词性从句的关联词大致相同，它们分别是：连词：that, whether, if；关系代词：who, what, which , whom, whose, whatever, whoever, whomever, whichever；关系副词：when, where, how, why, however, whenever, wherever。引导从句时一般不用逗号和主句分开。详细见下表：
1、that从句与wh-关系代词和关系副词引导名词性从句的区别
连词that在从句中不作成分，不含疑问意义；而wh-连词在从句中作成分，且含有疑问意义； 或what/where从句相当于一个名词后加一个定语从句。
It worried her a bit that her hair was turning grey.
她的头发在变白令她有点担忧。（that在从句中只起引导词作用，不作成分）
What caused the accident is still a complete mystery.
事故发生的原因仍然是个不解之谜。（What在从句中作主语）
2、that与whether引导名词性从句的区别。
that与whether都是连词，引导名词性从句时，在句中只起连接作用，都不担任句子成分，使用时有下列区别：
（1）动词doubt表示“怀疑、不知道” 解时，肯定句接whether引导的宾语从句； 否定句don’t doubt和疑问句Do you doubt要接that引导的从句。
I don’t doubt that he will come soon.我不怀疑他不久会来。（此处不用whether）
Can you doubt that he will win?你怀疑他会赢吗？（此处不用whether）
I doubt whether it is true.我怀疑那不是真的。
比较：doubt表示“不信”解时，表示强烈的不相信时，在陈述句中可接that从句。
I doubt that he will stay there.我不信他会留在那里。
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本文来源：http://www.gbppp.com/yl/462439/
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