表语从句详解.doc

1、表语从句详解一、概念表语从句是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+系动词+表语从句可以接表语从句的连系动词有be, look, remain, seem等.可以接表语从句的系动词有：1.be（being,been,am,is,are,was,were)2.feel,seem,look,appear,sound,taste,smell3.stand,lie,remain,keep,stay4.become,get,grow,turn,go,come,run,fall5.prove,turnoutThe trouble is that we are short of mo

2、ney.困难是我们资金短缺.That is why stone walls are used instead of fences around New England fields.这就是为什么在新英格兰用石头墙而不用栅栏的原因.At that time, it seemed as if I couldnt think of the right word anyhow.当时,我似乎怎么也想不出一个恰当的字眼来.引导表语从句的词：从属连词that、whether、as though、 as if（That引导表语从句时，在口语中，间或可以省略.）关系代词who, what, which, who

3、m, whose, whatever, whoever, whomever, whichever等；关系副词when, where, why, how, however, whenever, wherever等.由从属连词that，whether引导的表语从句.that在引导表语从句时无词义，而whether有词义，意为、是否.这时主句的主语常常是些抽象名词，如question(问题)，trouble(麻烦)，problem(问题)，result(结果)，chance(可能性)，suggestion(建议)，idea(想法)，reason(理由)等.表语从句对主句主语进行说明、解释，使主语的内

4、容具体化.例如：The trouble is (that) she has lost his money. 麻烦的事是他丢了钱.The question is whether we need more ice cream.问题是我们是否还需要一些冰淇淋.The problem was that it was too valuable for everyday use.问题是它作为日常之用太贵重了.What she couldnt understand was that fewer and fewer students showed interest in her lessons. 我们不能理解

5、越来越少的学生对他的课不感兴趣.由关系代词引导的表语从句.关系代词who, what, which, whom, whose, whatever, whoever, whomever, whichever等引导表语从句，在句中作主语、宾语、表语，关系代词不能省略.例如：The question is which of us should go.问题是我们哪一个应该去.The problem was who could do the work.问题是谁能做这项工作.Thats what he is worrying about.那就是他在担心的事.Thats what we should do.

6、那是我们应该做的.由关系副词引导的表语从句.关系副词 when, where, how, why 除在句子起连接作用外，在从句中还充当时间，地点，方式或原因状语，本身具有词义.例如：Go and get your coat. Its where you left it. 去把雨衣拿来.就在你原来放的地方.I had neither a raincoat nor an umbrella. Thats why I got wet through. 我们既没伞也没雨衣，这是我们淋湿的原因.That is how mice ruin many stores of grain every year.那就

7、是老鼠是怎样每年损害大量粮食的.That is what he is worried about.那就是他所担心的.由连词because，as if/as though等引导的表语从句.It looked as if it was going to snow.看起来好像要下雪了.Thats because we never thought of it.这是因为我们从未想过此事.It seems as if he didnt know the answer.好像他不知道答案.注意A. 表语从句一定要用陈述语序.False: The question is when can he arrive a

8、t the hotel. Right: The question is when he can arrive at the hotel.B. 不可以用if，而用whether 连接表语从句(as if 例外）.引导宾语从句时可以互换if/whether 位于介词后要用whether位于句首时要用whether.引导表语从句，主语从句，同位语从句时要用whether.False: The question is if the enemy is marching towards us.Right: The question is whether the enemy is marching towa

9、rds us.Right: It looked as if he had understood this question.C.不像宾语从句，在有表语从句的复合句中，主句时态和从句时态可以不一致.Right: The question is who will travel with me to Beijing tomorrow.Right: The question is why he cried yesterday.D. that在表语从句中不可以省掉.基本用法表语从句只能置于主句之后，而主句的动词只能是联系动词.名词性从句在be等系动词后作表语时被称为表语从句例如：The problem

10、is how we can get the things we need.问题是我们怎样能弄到我们需要的东西. (how 在表语从句中充当方式状语)The scissors are not what I need. 这把剪刀不是我所需要的.(what 在表语从句中充当宾语)What I told him was that I would find him a good play. 我告诉他的是我会给他找个好剧本.(what在主语从句中作直接宾语, that作为表语从句的引导词在该表语从句中不充当句子成分，不能省略)That is what I want to tell you.那就是我想要对你

11、讲的.(what在表语从句中充当直接宾语)That is why she failed to pass the exam. 那就是她考试不及格的原因.(why 在表语从句中充当原因状语)WhatItoldhimwasthatIwouldfindhimagoodplay.我告诉他的是我会给他找个好剧本.(what在主语从句中作直接宾语, that作为表语从句的引导词在该表语从句中不充当句子成分, 不能省略)ThatiswhatIwanttotellyou.那就是我想要对你讲的.(what在表语从句中充当直接宾语)Thatiswhyshefailedtopasstheexam.那就是她考试不及格的

12、原因.(why在表语从句中充当原因状语)注意Thatiswhy.是常用句型, 意为这就是的原因/因此, 其中why引导的名词性从句在句中作表语, 该句型通常用于针对前面已经说明过的原因进行总结, 又如：Thatiswhyyouseethisoldwomanbeforeyouknow,Jeanne.珍妮, 这就是现在这个老太婆出现在你面前的原因.(前文提到Jeanne对老妇人显得苍老憔悴深感诧异, 说话人对她讲述了其中的原因之后，用这一句来进行概括).ThatiswhyIcame.这就是我来的原因.下面是两个与Thatiswhy.形式相似的结构, 它们与Thatiswhy.结构之间的关系要能够辨

13、析清楚：(1)Thatiswhy.与Thatisthereasonwhy.同义, 只不过从语法结构上讲, Thatisthereasonwhy.中why引导的是个定语从句, 将其中的thereason去掉则与Thatiswhy.结构一样, 例如：Thatis(thereason)whyIcannotagree.这就是我不能同意的理由.(2)Thatisbecause.句型中从属连词because引导的名词性从句在此作表语, 这也是个常用句型, 意为这就是为什么/因为.Thatisbecause.与Thatiswhy.之间的不同在于Thatisbecause.指原因或理由, Thatiswhy.

14、则指由于各种原因所造成的后果, 例如：Hedidnotseethefilmlastnight.Thatisbecausehehadtohelphislittlesisterwithherhomework.昨天晚上他没有去看电影, 那是因为他得帮助他的妹妹做作业.(第一句话说明结果, 第二句话说明原因)Hehadseenthefilmbefore.Thatiswhyhedidnotseeitlastnight.他以前曾看过那部电影, 因此他昨天晚上没有去看.(第一句话说明原因, 第二句话说明结果)表语从句与宾语从句的关系宾语从句和表语从句都属于名词性从句.其作用跟名词在句中的作用相同.故充当宾语

15、的句子叫宾语从句，充当表语的句子叫表语从句.宾语从句(1)对于宾语从句要掌握以下三点语序:从句的语序必须是陈述句语序,即主语+谓语这种形式.时态:当主句是一般现在时或一般将来时的时候,从句可以是任何时态,而当主句是一般过去时的时候,从句,从句时态必须是过去时范围的时态,即(一般过去时,过去进行时,过去完成时,过去将来时).连接词:当从句意思完整,主句意思肯定时,连接词用that,且可以省去,当从句意思完整,主句意思不确定或含否定含意时,常用if或whether(是否),当从句意思不完整时,连接词则是代替不完整部分的特殊疑问词.表语从句在句子中起表语作用的从句叫做表语从句，位于主句系动词的后面.表语从句的引导词和主语从句的引导词相同.也是名词性从句的一种.如：Whatthepolicewanttoknowis