1、名词性从句的讲解及示意名词性从句的讲解及例题示范名词性从句的讲解及例题示范名词性从句，所起的作用其实相当于一个名词。象任何名词一样，名词从句也可用做动词的主语，但更多的用作动词的宾语，或用作动词 be 或其他系动词如 seem, appear 的表语，如：I know that he will come tomorrow. 我知道他明天会来。(宾语)That the famous film star will come excites many young people.那位著名影星要来的事令许多年轻人激动不已。 （主语）The question is whether they had sig
2、ned the contract.问题是他们是否已签了那个协议。 （表语）大致来说，名词性从句可分为四类：主语从句，表语从句，宾语从句，和同位语从句。下面分类叙述。一、主语从句1主语从句可分成如下几种：如果一个陈述句变成主语从句，由 that 引导。如：That he is the cleverest student in the school is known to all.众所周知他是学校里最聪明的学生。一般疑问句改成主语从句时，连接词通常用 whether, whether 后可跟 or not。Whether they will hold a meeting has not been
3、decided.要不要开会还没决定呢。特殊疑问句改成主语从句时，用疑问词 what, when, who, how, where 等引导。如： What he told you was only a lie.他跟你说的只不过是个谎言。When they will come isnt known now.他们什么时候来还不知道。2几个注意点由一般疑问句或特殊疑问句变过来的主语从句中需采用陈述句的形式。that 在句首时通常不省略。由一般疑问句变成主语从句时只能用 whether 而不能用 if。主语从句经常用 it 代替其句首的位置，以下是几个常见句型。It is + 形容词(interesti
4、ng, difficult, possible, surprising, clear, certain) + thatIt is + 动词的被动式（reported, announced, said, believed）+ thatIt is + 名词（a pity, fact, an honor, shame）+ that如：Its well known that China is growing stronger and stronger.众所周知，中国越来越强大了。Its said that he will be elected President.据说他将当选为总统。Its a pit
5、y that you cant come to my birthday party.很遗憾你不能来参加我的生日晚会。二、表语从句1.表语从句可以分为以下几种：由 that 引导。：如The difficulty is that no one wants to do that.困难在于没有人想干那件事。由关系代词 what 引起的This is what I want to tell you.这就是我想告诉你的事。由其他的连接代词或副词引导That is why he cries.那就是他为什么哭。This is how we can work out the problem.这就是我们如何解出
6、这个问题。2.注意事项：同主语从句一样，表语从句中的语序应该是陈述句的语序。表语从句中表是否只能用 whether。表语从句的常见句式：This is becauseThe reason for (or why) is that He looks as if三、宾语从句宾语从句一般也是由连词 that, where, if, who, whose, what, which, when,where, how, why 等引导。其选用规则跟主语从句，表语从句大致一样。1分类作动词的宾语I know that you will come at last.我知道你最后会来的。He asked me w
7、hat I want to read.他问我想读什么。作介词的宾语Pay attention to what the doctor said.注意医生说的话。2.注意点：宾语从句在疑问代词和副词之后应该用陈述句语序。主从句时态要一致。宾语从句中的 that 经常可省略。宾语从句中的 whether 可以用 if 代替。但是，如果有 or not, 一般不用 if，而用 whether. 此外，介词后带宾语从句中表是否时只能用 whether某些宾语从句,特别是带复合宾语的句子中,that 引导的从句常常移到后部去,前面用 it 作形式宾语.如:We all thought it a pity
8、that you hadnt taken part in the match.你没参加比赛,我们都觉得遗憾.I took it for granted that they were not coming.我想当然地认为他们会来。宾语从句前如有 think, believe, guess, suppose, expect, imagine 等词时,如果从句主语为 who, what 等疑问词均应提到句首.What do you think is fit for the post?你觉得谁适合这个职位?What can you guess is in the room?你猜屋子里有什么?在 thi
9、nk, believe, suppose, expect 等动词引导的宾语从句中,有时谓语尽管是否定的意思,却不用否定形式,而把 think 等动词改成否定式.即否定前置.I dont think you are right.我认为你不对.I dont expect well start at once.我认为我们可以不立刻动身.四、同位语从句在固定的一些词如 idea, fact, news, hope, belief, message, information, possibility, question, doubt, etc.之后用 that 或连接代词引起的从句作同位语。The fa
10、ct that he is the cleverest in the class is known to all.他是班上最聪明的这个事实众所周知。I am interested in the message that a famous star is coming tonight.我对今晚要来一明星的消息很感兴趣。下面是一些有关名词性从句的练习,请大家好好做一做.1.The trouble is _ we are short of money.a.why b.how c.that d.what2.China is no longer _.a.what it used to be b.what
11、 used to bec.what it used to like d.like it used to be3.Please tell me where _ from.a.do you comeb.b.you come c.c.are you comingd.d.you are coming4.He ran back into the room to see if he _ anything behind.a.has forgottenb.had forgottenc.has left d.had left5.Do you know the reason _ he was late for s
12、chool?a. whyb. for thatc. whichd. for which6.He is not the man _ he used to be.a.whatb.whichc. whomd. whose7.His family had almost forgotten _ like.a. how his face wasb. which was his facec. that his face wasd. what his face was8._ appeared that he was talking to himself.a. He b. It c. What d.That9.
13、The news _ we are invited to the lecture is very encouraging.a. that b. which c. if d. whether10.The fact _ in the past few years proves that our Partys policy is correct.a.that great achievement was madeb.which great achievements were madec.what have been maded.that great achievements have been madeKey: 1.c 2.a 3.c 4. 5.d 6.c 7.d 8.b 9.a 10.d
