高中英语语法 名词性从句

1、一.名词性从句简介1、主语从句作句子主语的从句叫主语从句。主语从句通常由连接词 that , whether , if; 连接 代词 what , whatever , who , whoever , which; 连接副词 how , when , where , why 等词引导。例如:What he wants to tell us is not clear. / Who will win the match is still unknown.(1 主语从句可以位于句首,但有时为避免句子头重脚轻,常用 it 代替主语从句 作形式主语放于句首, 而把主语从句置于句末。 主语从句后的谓语动词

2、一般用单 数形式。That the earth is round is true. = It is true that the earth is round.Whether he will come hasnt been decided. = It hasnt been decided whether he will come.常用句型如下: It + be + 名词 /形容词 + that从句It is a pity that we cant go. It is clear that Tom has returned. It + be + 动词的过去分词 + that从句 It is sai

3、d / reported / believed / known that It + 不及物动词 + that 从句另 :在主语从句中用来表示惊奇、不相信、惋惜、理应如此等语气时,谓语动词 要用虚拟语气 “(should +do” ,常用的句型有:It is necessary (important, natural, strange, etc. that sb. should do sth. It is a pity (a shame, no wonder, etc. that sb. should do sth.It is suggested (requested, proposed, ad

4、vised, etc. that sb. should do sth. (2 主语从句不可位于句首的五种情况: It is said /reported that 结构中的主语从句不可提前。例如:It is said that President Jiang will visit our school next week.That President Jiang will visit our school next week is said. × It happens/occurs 结构中的主语从句不可提前。例如:It occurred to him that he failed i

5、n the examination.That he failed in the examination occurred to him. × It doesnt matter how/whether 结构中的主语从句不可提前。例如:It doesnt matter whether he is wrong or not. Whether he is wrong or not doesnt matter. × 含主语从句的复合句是疑问句时,主语从句不可提前。例如:Is it likely that it will rain in the evening? Is that it

6、will rain in the evening likely? × if 引导的主语从句It is not clear to me if she likes the present. If she likes the present is not clear to me. ×注意:(1连词 that, whether在主语从句中不担任句子成分,只起连接作用,不 能省略。并且 whether 引导主语从句时不能用 if 代替。(2连接代词 who, which和连接副词 how, when, where, why在句中既保留自己 的疑问含义、又起连接作用,在主语从句中充当主

7、语,宾语,状语,不能省略。 可以用形式主语 it 引导。(3who, whom, which, what等可以和 ever 构成合成词,引导主语从句和宾语从 句。此类主语从句不能用 it 引导,引导词在句中担任句子成分,不能省略。 2、宾语从句在复合句中用作宾语的从句是宾语从句 ; 在句中可以作谓语动词或介词及非谓语 动词的宾语。 引导宾语从句的关联词与引导主语从句, 表语从句的关联词大致一 样。1. 由连接词 that 引导的宾语从句连接词 that 引导宾语从句时, that 在句中不担任任何成分, 在口语或非正式的文 体中常被省去,但如从句是并列句时 , 第二个分句前的 that 不可省

8、。例如: He has told me (that he will go to Shanghai tomorrow and that he has got everything ready.2. 用 who , whoever, whom, whose, which, whichever , what, whatever, when , where, why, how等关联词引导的宾语从句相当于特殊疑问句,应注意句子语序 要用陈述语序。例如:She always thinks of how she can work well.She will give whoever needs help a

9、 warm support.3. 用 whether 或 if 引导的宾语从句,其主语和谓语的顺序也不能颠倒,仍保持 陈述句语序。此外, whether 与 if 在作 “ 是否 ” 的意思讲时在下列情况下一般只能 用 whether ,不用 if :a. 引导主语从句并在句首时; b. 引导表语从句时; c . 引导从句作介词宾 语时;d. 从句后有 “or not” 时; e. 后接动词不定式时。Whether there is life on the moon is an interesting question.The question is whether she should ha

10、ve a low opinion of the test.Everything depends on whether we have enough money.I wonder whether he will come or not. Can you tell me whether to go or to stay?4. 注意宾语从句中的时态呼应,当主句动词是现在时,从句根据自身的句子情 况,而使用不同时态。例如:I know (thathe studies English every day. (从句用一般现在时I know (thathe studied English last term

11、. (从句用一般过去时I know (that he will study English next year. (从句用一般将来时I know (thathe has studied English since 1998. (从句用现在完成时 当主句动词是过去时态(could, would除外,从句则要用相应的过去时态,如 一般过去时, 过去进行时, 过去将来时等; 当从句表示的是客观真理, 科学原理,自然现象,则从句仍用现在时态。例如:The teacher told us that Tom had left us for America.5. think, believe, expect

12、 , imagine, suppose等动词引起的否定性宾语从句中, 要把上述主句中的动词变为否定式,即将从句中的否定形式移到主句中。例如: We dont think you are here. I dont believe he will do so. 3.同位语从句如果担任同位语的是个句子, 则这个句子是同位语从句。 同位语从句表示先行名 词的具体内容, 常见的能跟同位语从句的名词有 news 、 fact, problem , question、 wish 、 hope 、 idea 、 information 、 advice 、 suggestion 、 truth 、 word,

13、 promise、 belief, doubt, demand、 message 、 order 、 thought, reply, reason ,request、 rumour 、等。引导同位语从句常用连词 that , 它在句中不担任句子成分,没有词 意。除 that 外,还有 whether, when, where, who, what, which, why, how等。 同位语从句与先行名词有时也可以分开。The news that we won the game is exciting. I have no idea when he will come back home.Th

14、e thought came to him that Mary had probably fallen ill. They have no hope that he will recover.注:同位语从句与定语从句的区别:(1同位语从句的先行名词极为有限,而定语从句的先行词则不计其数。(2引导同位语从句的连词 that 没有实际意义,在句中不担任句子成分,一般 不能省略。而引导定语从句的 that 则在从句中作主语,宾语等 (在从句中作宾语 时可以省略; 。引导同位语从句的 wh 一词多具有疑问意义,而引导定语从句 的 wh 一词则没有疑问意义。I had no idea that you

15、were here.(that 引导同位语从句,不能省略Have you got the idea(that this book gives you of life in ancient Greece? (that 引导定语从句,作宾语,可以省略(3同位语从句与先行名词是等同关系,一个抽象,一个具体,两者常可以转 述为主表关系,定语从句与先行词是修饰与被修饰关系。The news that our team won the game is true.= The news is that our team won the game. (同位语从句 The news that you have h

16、eard isnt true. (定语从句 (4 when 和 where 引导的同位语从句与定语从句的区别。when 和 where 前面的名词若是表示时间、地点的名词,则 when 和 where 引 导的是定语从句,否则为同位语从句。如:They put forward the question where they could get the money.( 同位语从句 This is the place where the accident happened.( 定语从句 4.表语从句在句中作表语的从句叫表语从句。 它常位于句中联系动词或是起联系动词作用的 动词之后。引导表语从句的关

17、联词与引导主语从句的关联词大致一样,The fact is that we have lost the game. Thats just what I want.This is where our problem lies. The problem is where we can hold our meeting.That is why he didnt come to the meeting.seem, look, as if, because等词均可引导表语从句:It seems that /looks as if it is going to rain. It was because I

18、 got up late. 注意 :当主语是 reason 时,表语从句要用 that 引导而不是 because 。例如: The reason why he was late was that (不能省略 he missed the train by one minute this morning.同位语从句讲义及练习一、理解同位语从句的含义,把握同位语从句的实质在主从复合句中作同位语的从句称为同位语从句。同位语从句一般用 that, whether , what, which, who, when, where, why, how 等词引导,常放在 fact, news, idea, t

19、ruth, hope, problem, information, wish,promise, answer, evidence, report, explanation, suggestion, conclusion 等抽象名词后面,说明该名词的具体内容。换言之, 同位语从句和所修饰的名词在内容上为同一关系,对其内容作进一步说明。例:The news that they had won the game soon spread over the whole school.他们比赛获胜的消息很快传遍了整个学校。析:they had won the game说明 The news的全部内容,因此

20、该句为同位语从句。 二、正确运用同位语从句的引导词,准确把握同位语从句1. 如同位语从句意义完整,应用 that 引导同位语从句。(即 that 不充当任何成分, 只起连接作用,不可省略例:The general gave the order that the soldiers should cross the river at once.将军下达了战士们立即过河的命令。析:the soldiers should cross the river at once是 the order的全部内容, 且意义完整,因此应用 that 引导同位语从句。2. 如同位语从句意义不完整,需增加 "

21、是否 " 的含义,应用 whether 引导同位语从句。 (if 不能引导同位语从句例:We'll discuss the problem whether the sports meeting will be held on time. 我们将讨论运动会是否会如期举行的问题。析:the sports meeting will be held on time意义不完整,应加 " 是否 " 的含义 才能表达 the problem的全部内容,因此应用 whether 引导同位语从句。3. 如同位语从句意义不完整,需增加 " 什么时候 " 、

22、 " 什么地点 " 、 " 什么方式 " 等含义, 应用 when, where, how等词引导同位语从句。例 1:I have no idea when he will be back.析:he will be back意义不完整,应加 " 什么时候 " 的含义才能表达 idea 的全部 内容,因此应用 when 引导同位语从句。例 2:I have no impression how he went home, perhaps by bike.析:he went home意义不完整,应加 " 如何 " 的含义

23、才能表达 impression 的全部内容, 因此应用 how 引导同位语从句。4. 当主句的谓语较短,而同位语从句较长时,同位语从句常后置。如:The thought came to him that maybe the enemy had fled the city. 三、把握同位语从句和定语从句的区别,明确同位语从句和相似从句的界限同位语从句和定语从句相似,都放在某一名词或代词后面,但同位语从句不同于定语 从句。 同位语从句对名词加以补充说明, 是名词全部内容的体现, 且名词和同位语从句的引 导词均不在从句中作成分; 定语从句说明先行词的性质与特征, 与先行词是修饰与被修饰的 关系,且名

24、词和定语从句的引导词均在从句中作成分。区分时可以在先行词与与从句之间加一个系动词 be, 使之构成一个新句子, 如果句子通 顺且符合逻辑,则为同位语从句,反之,则为定语从句。如:The report that he was going to resign was false.因为 the report was that he was going to resign 句意通顺, 所以, that he was going to resign 是同位语从句。例 1:1 Information has been put forward _ more middle school graduates w

25、ill be admitted into universities.A. while B. that C. when D. as析:答案为 B 。 more middle school graduates will be admitted into universities 是 Information 的内容, 且 Information 不在从句中作成分, 所以该句为同位语从句。 应将 该句区别于:2）It is said that more middle school graduates will be admitted into universities，this is the info

26、rmation _ has been put forward. A. what B. that C. when D. as 析：答案为 B。that has been put forward 为 information 的修饰性定语，且 information 在从句中作主语，所以该句为定语从句。 例 2：She heard a terrible noise,_ brought her heart into her mouth.(MET91 A. it B. which C. this D. that 析：答案为 B。分析语境含义、句子结构和句子成分可知，该句为非限制性定语从 句，先行词为 a

27、 terrible noise，且它在从句中作主语。应将该句区别于： I can't stand the terrible noise _ she is crying loudly. A. it B. which C. this D. that 析： 答案为 D。 is crying loudly 是 the terrible noise 的内容， the terrible she 且 noise 不在从句中作成分，所以该句为同位语从句。 巩固性练习： 1. The fact _ she works hard is well known to us all. A. that B. wh

28、at C. why D. which 2. The fact _ he was successful proves his ability. A. hat B. what C. which D. why 3. The news _ he was kidnapped surprised us greatly. A. what B. that C. why D. when 4. His suggestion _ the meeting be delayed was turned down. A. which B. that C./ D. it 5. I have no idea _ he will

29、 start. A. when B. that C. what D./ 6. I've come from the government with a message _ the meeting won't be held tomorrow. A. if B. that C. whether D. which 7. The thought _ he might fail in the exam worried him. A. when B. which C. what D. that 8. The order _ the prisoner be set free arrived

30、 too late. A. which B. whether C. that D. what 9. The nurses are trying their best to reduce the patient's fear _ he would die of the disease. A. that B. as C. of which D. which 10. He often asked me the question _ the work was worth doing. A. whether B. where C. that D. when Keys: 1-5 AABBA 6-1

31、0 BDCAA 同位语从句和定语从句的三点区别 同位语从句和定语从句很相似,但还是有区别的,区别主要在以下三方面: 1. 从词类上区别 同位语从句前面的名词只能是 idea,fact,news,hope,belief,suggestion,proposal,word,thought,doubt,truth,possibi lity,promise,order 等有一定内涵的名词?而定语从句的先行词可以是名词?代词?主句的 一部分或是整个主句?如: The possibility that the majority of the labour force will work at home is

32、 often discussed. (同位语从句 We are not looking into the question whether he is worth trusting. (同位语从句 Word came that he had been abroad. (同位语从句 Our team has won the game, which made us very happy. 我们的队赢了,这让我们很高兴?(定语从句 The doctor whom you are looking for is in the room. 你找的那位医生在房间里面?(定语从句 His mother did all she could to help him with his study.他妈妈尽她的最大努 力帮助他的学习?(定语从句,代词 all 作先行词? 2. 从性质上区别 定语从句是从句对其先行词的修饰或限制,属于形容词性从句的范畴;而同位语从句是 从句对前面抽象名词的进一步的说明和解释,属于名词性从句的