人教版高中英语语法认识名词性从句.doc

认识名词性从句在复合句中起名词作用的从句叫做名词性从句。所以名词性从句都用陈述句语序。它包括主语从句、宾语从句、表语从句和同位语从句。1.引导名词性从句的连接词可分为三类：连接词：that, whether, if （不充当从句的任何成分）连接代词：what, who, whom , whose, which，whichever，whatever，whoever，（在从句中可充当主语，宾语，定语） 连接副词：when, where, how, why，whenever，wherever，however（在从句中可充当状语）2. 名词性从句中的时态准确运用和，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 (that) he will study English next year. （从句用一般将来时）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 America3.语气：（1）.当名词性从句表肯定，事实的用that作连接词，当带有疑问语气，不确定的用疑问词作连接词，（2）在表命令，要求，建议的名词性从句中用should+动词原形表虚拟，如：A.It is suggested (requested, proposed, desired, etc.) that（should）do(主语从句)B. demand/order/suggest/ insist/ demand/ request/ command +that + sb（should）do+（宾语从句）I insist that she (should) do her work alone. 我坚持要她自己工作。The commander ordered that troops (should) set off at once. 司令员命令部队马上出发。一 主语从句作句子主语的从句叫主语从句。（主语从句通常由从属连词that，whether，if和连接代词what，who，which，whatever，whoever以及连接副词how，when，where，why等词引导。）that在句中无词义，只起连接作用；连接代词和连接副词在句中既保留自己的疑问含义、又起连接作用，在从句中充当从句的成分。主语从句后的谓语动词一般用单数形式例如：What he wants to tell us is not clear. 他要跟我们说什么，还不清楚。It is known to us how he became a writer. 我们都知道他是如何成为一名作家的。Where the English evening will be held has not yet been announced. 英语晚会将在哪里举行，还没有宣布。有时为避免句子头重脚轻，常用形式主语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。常用句型如下：（1）It + be + 名词 + that从句（2）It + be + 形容词 + that从句（3）It + be + 动词的过去分词 + that从句（4）It + 不及物动词 + that 从句如：It is necessary (important, natural, strange, etc.) that we should finish the homework. It is a pity (a shame, no wonder, etc.) that he failed the exam. 二. 宾语从句名词句用作宾语的从句叫宾语从句。（1）. 由连接词that引导的宾语从句由连接词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。例如：He has told me （that） he will go to Shanghai tomorrow and that he will stay there for a week.We must never think (that) we are good in everything while others are good in nothing. 我们决不能认为自己什么都好，别人什么都不好。（2）. 用who，whom, which, whose, what, when, where, why, how, whoever, whatever, whichever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：I want to know what he has told you. 我想知道他告诉了你什么。 She always thinks of how she can work well. 她总是在想怎样能把工作做好。She will give whoever needs help a warm support. 凡需要帮助的人，她都会给予热情的支持。（3）. think, believe, imagine, suppose等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. 我们认为你不在这。I dont believe he will do so. 我相信他不会这样做。三. 表语从句在句中作表语的从句叫表语从句。表语从句位于be，appear，seem等连系动词后，有时用as if引导。其基本结构为：主语 + 系动词 + that从句。例如：The fact is that we have lost the game. 事实是我们已经输了这场比赛。 That is why he didnt come to the meeting. 那就是他为什么不到会的原因。It looks as if it is going to rain. 看上去天要下雨了。需要注意的是，当主语是reason时，表语从句要用that引导而不是because。例如：Why he was so late ?The reason was that he missed the train by one minute this morning 四. 同位语从句（说明其前面的名词的具体内容。）1. 先行词常是抽象名词：advice、fact、hope、idea、information、news、order、problem、promise、question、request、suggestion、truth、opinion等，如：The news that we won the game is exciting. 我们赢得这场比赛的消息令人激动。I have no idea when he will come back home. 我不知道他什么时候回来。（再次强调：当名词性从句表肯定，事实的用that作连接词，当带有疑问语气，不确定的用疑问词作连接词）2. 同位语从句分隔现象：（也是为了避免头重脚轻的）The thought that Mary had probably fallen ill came to him.(英语中不会这么表达) 而是： The thought came to him that Mary had probably fallen ill. 他想到可能玛丽生病了。3.同位语从句和定语从句的区别：从意思上判断，看它是解释作用还是修饰作用 ，解释则为同位语从句，修饰形容则为定语从句试比较下面两个例句: I had no idea that you 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）that作为关系代词，可以引导定语从句，充当句子成分，在从句中作宾语时可以省略； that引导同位语从句时，起连词的作用，没有实际意义，不充当句子成分，一般不能省略。 区分： 一，whether与if： 1.当它们都在作“是否”的意思讲时，在下列情况下一般只能用whether，不用if：a whether or not （whether 和if都可以和or not连用,但是whether之后可以直接跟or not）bwhether to do c.介词后只能用whether d. 主从，表从，同位语从一般只用whether例如：I dontcarewhetherornotitwillrain.(不用if)I cant decide whether to stay.我不能决定是否留下.Whether there is life on the moon is an interesting question. 月球上有没有生命是个有趣的问题。 Everything depends on whether we have enough money. 一切要看我们是否有足够的钱。）2.if还可以表示“如果”的意思，但whether没有，所以当表示如果时，只能用if，如：Please tell me if he comes.=If he comes ,please tell me.Q:体会If在不同句子中意思的区别：Please tell me if he will come.(宾语从句) Please tell me if he comes.(条件状语从句)3.whether 有“无论”的意思：Whether you are a student or a teacher ,you should obey the school rules .二，what与that从句：1.what从句：只引导名词性从句 在从句中有充当成分 可带有疑问意义或不带疑问意义时解释为“的东西/事物”，如I dont know what we should buy for the party.(有疑问意义，我不知道我们应该为聚会买些什么东西。)You can eat what was on the table.（没有疑问意义，你可以吃放在桌子上的东西。）2.that从句：引导定从，名从 在定从中有充当成分，在名从中没有充当成分三，疑问词-ever引导的名词性从句 可以转化为 n.+定语从句，如：whoever = any person who/the person or people whowhatever = anything thatwhichever =any thatwherever = any place whereWhoever wants to see this film can go with us tonight.=Anyone who wants to see this film can go with us tonight.无论谁想看这部电影， 今晚都可以和我们一起去。You can give the ticket to whomever you like.You can give the ticket to anyone whom you like. 你可以把票给任何你想给的人。You may borrow whichever (book) you like.You may borrow any book which you like . 所有的书都在这儿， 你愿借哪本就借哪本。Ill do whatever you ask me to do. Ill do anything that you ask me to do.你叫我做什么， 我就做什么名词性从句专项练习What/that的区别：1._ he wants is a book.2. _ he wants to go there is obvious.3. The result is _ we won the game.4. This is _ we want to know.5. Is _ he told us true?6. We should pay attention to _ the teacher is saying.7. I have no idea _ he did that afternoon.9._ has made China_ it is now?10、_ you have done might do harm to other people. 11、_ we cant get seems better than _ we have. 12、_ he said at the meeting astonished everybody present.）