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. 主语从句

　　主语从句在句中做主语。它可以放在主句谓语动词之前，但多数情况由 it 作形式主语，而把主语从句放在主句之后。

　　①What we will do next is unknown to all. 接下来做什么大家都不知道。

　　②It is a pity that you should miss the bus. 真遗憾，你错过了那班公共汽车。

　　2. 表语从句

　　表语从句在句中作表语，位于主句中的系动词之后，如：

　　The question is who can complete the difficult task . 问题是谁能完成这项艰巨的任务。

　　表语从句还可用 as if引导。

　　He looked as if he was going to impress everything in the room into his mind.

　　他看上去是要把屋里的一切都印入脑海。

　　3. 同位语从句

　　同位语从句跟在名词后面，进一步说明该名词的具体内容。

　　引导同位语从句的名词主要有 fact, news, promise, idea, truth等。连接词用 that, 不用 which。

　　①His delay is due to the fact that the car went wrong halfway.

　　他拖延了时间是因为半路上车坏了。

　　②The news that our team has won the match is true. 我们队赢得比赛的消息是真的。

　　当从句前面的名词为idea 时， 从句也可以用how, what, when, why等引导。

　　①You have no idea how worried I was then. 你不知道当时我又多么担心。

　　②I have no idea where he has gone and when he will come back.

　　我不知道他去了哪里，也不知道他什么时候回来。

　　4. 宾语从句

　　(1)宾语从句在句中作及物动词或介词的宾语。

　　①We can learn what we did not know. 我们可以学习我们所未知的。

　　②He was very pleased with what you had said at the meeting. 他对你会上所言十分满意。

　　如果主句的谓语动词是及物动词make, find, see, hear等，则把宾语从句置于宾语补足语之后，用it 作为形式宾语。

　　We find it necessary that we practise spoken-English every day.

　　我们发现每天练习英语口语是很必要的。

　　另外，某些带宾语的形容词，如 sure, happy, glad, certain等之后也可带宾语从句。(注：有的语法学家认为是省略了形容词后的介词) 。

　　I am sure that he will succeed. 我相信他会成功的。

　　注意(1)关联词只能用 whether 不能用 if 表示“是否”的情况如下：

　　A. 在表语从句和同位从句中。

　　①The question is whether the film is worth seeing. 问题是这部电影是否值得一看。

　　②The news whether our team has won the match is unknown.

　　我们队是否赢得比赛的消息还是未知的。

　　B. 在主语从句中，只有用it 作形式主语时，whether 和if都能引导主语从句，否则，也只能用 whether。

　　①Whether we shall attend the meeting hasn’t been decided yet.

　　②It hasn’t been decided whether (if) we shall attend the meeting.

　　我是否出席会议还没有决定。

　　C. 在介词之后。(介词往往可以省略)。

　　It all depends (on) whether they will support us. 这完全在于他们是否支持我们。

　　(2)关联词if, whether均可使用的情况如下：

　　A. 引导宾语从句。

　　I wonder if (whether) the news is true or not. 我琢磨这个消息是否属实。

　　B. 在“be＋形容词”之后。

　　He was not sure whether (if)it is right or wrong. 他不能确定那是对还是错。

　　(3)关联词只能用whether或if, 不能用that 的情况如下：

　　若doubt一词作“怀疑”解接宾语从句时，主语为肯定句用whether或if, 主句为否定句或疑问句用that。

　　①I doubt whether he will come soon. 我怀疑他是否会很快来。

　　②I do not doubt that he will come soon. 我不怀疑他会很快来。

　　③Do you doubt that he will come soon? 你怀疑他是否会很快来。

　　注意：下面这个例句中doubt的含义为“认为……未必可能”。

　　I doubt that he will come. 我怀疑他未必会来。

　　直击高考

　　1. —Are you still thinking about yesterday’s game ?

　　—Oh, that’s _____. (2003北京)

　　A. what makes me feel excited B. whatever I feel excited about

　　C. how I feel about it D. when I feel excited

　　2. It worried her a bit ____ her hair was turning grey. (MET1992 )

　　A. while B. that C. if D. for

　　3. _____ we’ll go camping tomorrow depends on the weather. (NMET 96 )

　　A. If B. Whether C. That D. Where

　　4. ____ she couldn’t understand was ____ fewer and fewer students showed interest in her lessons. (2000上海)

　　A. What…why B. That…what C. What…because D. Why…that

　　5. Someone is ringing the doorbell. Go and see____. (2000上海)

　　A. who is he B. who he is C. who is it D. who it is

　　6._____ we can’t get seems better than ____we have. (NMET1996)

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

　　7. It is generally considered unwise to give a child _____he or she wants. (NMET 1997)

　　A. however B. whatever C. whichever D. whenever

　　8. Sarah hopes to become a friend of ____ shares her interests. (1995 上海)

　　A. anyone B. whomever C. whoever D. no matter who

　　答案与分析

　　1. A 本题考查表语从句的用法。引导词在从句中做主语，因此用what引导。

　　2. B该题考查考生对主语从句的掌握情况。对此题只要考生判断出It为本句的形式主语，而要选的词引导的是主语从句作真正主语，故that是正确选择。该句意思是：“她头发日渐灰白使她有些担忧。”

　　3. B A有一定干扰性，whether在这里引导定语从句，位于句首时不可以用if代替。

　　4. A 此题前一个空为连接代词引起一个主语从句，第二空为连接副词引起一表语从句。根据句子所要表达的意思，只能选A。

　　5. D 此题考查名词性从句中，who 引起一宾语从句的用法。在宾语从句中要注意语序的问题。

　　6. A该题考试目标是要考查考生对名词性从句中连接代词用法的掌握。What引导主语从句，在从句中作said的宾语，即，“他在会上的发言使到会的每位大为吃惊。”

　　7. B本题考查从属关联词的用法。Whatever意为anything that，everything that.选whatever句意清晰，句子结构正确。

　　8. C whoever引导宾语从句作介词of 的宾语，whoever在宾语从句中作shares动词的主语。D项no matter who不能引导宾语从句，A项不可作引导词，B项是宾格形式不可作主语。

　　专项训练

　　1. ____leaves the room last ought to turn off the lights.

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

　　2. Father made a promise ____ I passed the examination he would buy me a bicycle.

　　A. that B. if C. whether D. that if

　　3. _____you don’t like him is none of my business.

　　A. What B. Who C. That D. Whether

　　4. _____the old man’s sons wanted to know was _____ the gold had been hidden.

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

　　5. He told us ____ he had done.

　　A. that all B. all what C. all which D. what all

　　6. He always thinks of ____ he can do more for the people.

　　A. what B. how C. if D. whatever

　　7. Our hometown is quite different from _____ before.

　　A. that it was B. what it was

　　C. which it was D. when it was

　　8.____surprised us very much that Tom should have left without a word.

　　A. He B. It C. This D. That

　　9. Things were not ____ they had been before.

　　A. as B. because C. that D. where

　　10. He was ill. That is _____ he didn’t come yesterday.

　　A. when B. why C. how D. that

　　11. The fact _____ he didn’t see Lao Li yesterday is true.

　　A. which B. that C. when D. what

　　12. I have no idea ______ he will come back.

　　A. where B. when C. what D. that

　　13. No one can tell ____ will happen next.

　　A. what B. when C. where D. which

　　14. It is generally considered unwise to give a child ____ he or she wants.

　　A. however B. whatever C. whichever D. whenever

　　15. She had demanded to know____ the child was.

　　A. that B. which C. whose D. whom

　　16 ____ he said in the office made everybody present very surprised.

　　A. What B. That C. The fact D. The matter

　　17.____ we can’t get seems better than ___ we have.

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

　　18. It worried her mother a bit___ her hair was turning grey.

　　A. while B. that C. if D. for

　　19. —Do you remember ___ our manager came ?

　　—Yes, I do, he came in his car.

　　A. how B. when C. that D. if

　　20. Please go and bring your pen here. It’s ____ you left it.

　　A. there B. where C. there where D. where there

　　答案与分析

　　1. D whoever引导主语从句，兼作先行词和关系词， 意思是“凡是……的人”，等于anybody who。句意是：最后一个离开房间的人应该把灯关掉。

　　2. D that 引导同位语从句，说明promise的内容； 在that从句中，if 引导条件状语从句。

　　3. C 本句的谓语动词是is, 前面是一个主语从句； you don’t like him是一个意思完整的句子，从句不需要任何有词义的连词引导，that只起连接作用，无词义，所以选C。

　　4. B what引导主语从句在从句中作宾语；where引导宾语从句。

　　5. B all 是us 的同位语，其后的 what 引导宾语从句。 句意是：他把所做的事告诉了我们所有人。

　　6. B从句中谓语动词 do 已有宾语 more, 可排除 A 和 D; 在介词之后要用 whether而不用 if 引导宾语从句，所以选B。

　　7. B what 引导的从句作介词的宾语，并在从句中兼作宾语，而 that, which, when 则不能。

　　8. B It 作形式主语，引导主语从句， This, That不能作形式主语。

　　9. A as 引导表语从句。表示“象……那样子”。

　　10. B why 引导表语从句，表示“(有病的)结果”， that表原因。

　　11. B同位语从句说明 fact 的具体内容，只用 that 引导，不能省略。that只起连词作用，不作句子成分。

　　12. B 用 when 引导同位语从句，表示将回来的时间，A, C,D三项均与题意不符。

　　13. A 宾语从句中缺少主语，填which 意义不通， when 和where在从句中只能作时间、地点状语。

　　14. B whatever引导宾语从句，在从句中作wants的宾语， 用 whichever引导，则表示“任何哪个”，与题意不符，A,D都只能作状语。

　　15. C whose 在宾语从句中作表语。

　　16. A what在此作连接代词，引导主语从句，且在从句中作宾语。

　　17. A 第一个what引导的主语从句作主句的主语；第二个what引导的主语从句作比较状语从句的主语。两个what均在各自引导的从句中作宾语。

　　18. B that在此引导主语从句；句首的it 为形式主语。

　　19. A由答语后半部分的大意即可选定答案。

　　20. B where在此处作连接副词，引导表语从句且在从句中作状语。