高中名词性从句讲解.doc

名词性从句一.概念 名词性从句共有四种:主语从句,表语从句,宾语从句和同位语从句1 主语从句：主语从句在整个句子中作主语。(1)that不同于其它的连词，它不充当句子的成分，只是单纯的连接词，通常不可以省略。从句置于句首时，绝对不可以省略。That the driver could not control his war was obvious.It was obvious that the driver could not control his car.（形式主语it）(2)if 不能用在主语从句中，而是用whetherWhether he left (or not) is unknown(3)当主语从句作主语时，谓语动词一般用（dose），下面这个句型例外。What we need is more time and money.What we need are many more books.（就近原则）2.表语从句：表语从句出现在系动词后，充当表语。The trouble is that we are short of money.（不可省略）Go and get your coat. Its where you left it.（陈述句语序）(1) 引导表语从句除了上述三类词外还有because, as if/ as though等等The reason (why/for which.) is that It/This/That is because(2) 连系动词“appear, look, seem”的两个常用句型It seems/appears that.It looks/seems as if/as though(与事实相符用陈述语气，与事实相反用虚拟语气)It looked as if it was going to rain. 看起来天要下雨了。(3) as 也可以引导表语从句Things are not always as they seem to be3. 宾语从句：及物动词，形容词和介词后加宾语从句作其宾语。(1) 宾语从句时态与主句一致，但宾语从句表示的是客观真理或普遍现象除外The teacher told us that the earth moves around the sun(2) 连词whether和 if可以互换，但注意下列情况注：连词后紧跟or not；作介词宾语；连接词后直接加不定式；仅能用whether1）I want to know whether or not they will come.2）He was interested in whether he saw her there.3）He doesnt know whether to stay or not.如果宾语从句是否定时，一般用if引导I care if he will not attend the meeting.(3) 当宾语从句后带宾补时，要用“主语+谓语+it +宾补+that-clause,that不可省略I think it certain that she will do well in her exam.(4) 当主语是I, we ，主句用think, believe, suppose, expect, imagine五个动词时，用否定转移I dont think he will win the game, will he?(5) that在宾语从句常可以省略，但由and或 but连接两个或多个宾语从句时，仅可以省略第一个连词thatHe said (that) he had eaten nothing but that he wasnt hungry.Everybody could see what happened and that Tom was frightened.(6)that引导的宾语从句作介词宾语时，that不能省略。I know nothing about him except that he is from the south.(7) 主句谓语动词与that从句之间有插入语，that不可省略。We decided, in view of his special circumstances, that we would admit him for a probationary period. 鉴于他的特殊情况，我们决定应允他一段试用期。4. 同位语从句，在句中作某些名词的同位语，对前面的名词进一步说明。用在下列名词 fact,news,idea,hope,believe,hope,thought（想法）,doubt.truth,order（命令）,suggestion（建议；暗示）。在一些表示“建议、劝说、命令”的名词后面的从句中，谓语动词用虚拟语气。should+动词原形表示，should可省略。如：My suggestion is that we (should) start early tomorrow. 我的建议是我们明天一早就出发。(1) There is no doubt that he will come.There is doubt whether he will come.Word came that Napoleon would come to inspect them.There is no possibility that.(2) that引导的同位语从句与定语从句的区别：在同位语从句中：that不可以省略，不作成分;定语从句的关系代词that在定语从句作成分，作宾语时可以省略We are interested in the news that some foreigners would visit our school.We are interested in the news（that ）he told us.when, where引导的同位语从句与定语从句的区别：在定语从句中，when, where前有分别表示时间、地点的先行词；而在同位语从句中无此对应关系They have no idea at all where he has gone.(同位语从句)Go and get your coat. Its in the place where you left it.(定语从句)5. 疑问词-ever既可以引导名词性从句，也可以引导让步状语从句，而no matter+疑问词只能引导让步状语从句No matter where I go, my heart is towards China.I believer whatever he says. （？） Whatever he says, I will never believe him.who与 whoever的区别 who是“谁”的意思，表示具有疑问，whoever相当于anyone who“无论谁”Whoever leaves the room last ought to turn off the lights.Can you tell me who that gentleman is?6当名词性从句缺少主语、宾语或表语时，引导词通常用what，它相当于。（另外，有时具有感叹意义all that, anything that或 the thing(s) that）What we cant get seems better than what we have.Tom thought what a beautiful girl Mary was.7.注意区分it 作形式主语的主语从句与强调句强调句句型It is/was+被强调部分+that, 去掉It is/was, that，句子仍然成立。It is natural that they should have different views. 主语从句It is only lately that he had had a family himself. 强调句What was it that he wanted? I dont know what it was that he wanted.It was in the hotel where he stayed that we discussed the serious problem8.注意it 作形式主语的主语从句和as引导非限制性定语从句引导的不同It is known to all that the earth is round.As is known to all.the earth is round。补充名词性从句资料：1主语从句能用it作形式上的主语。常以it作形式主语的句型有：A.It+be+形容词(obvious, true, natural, surprising, good, wonderful, funny, possible, likely, certain, probable, etc.)+that从句。如：It is certain that she will do well in her exam. 毫无疑问她考试成绩会很好。B. It+be+名词词组(no wonder, an honour, a good thing, a pity, no surprise, etc.)+that从句。Its a pity that we cant go. 很遗憾我们不能去。Its no surprise that our team should have won the game. 我们没赢这场比赛真意外。C.It+be+过去分词(said, reported, thought, expected, decided, announced, arranged, etc.)+that从句。It is said that Mr. Green has arrived in Beijing. 据说格林先生已经到了北京。D. It+seem, happen等不及物动词及短语+that从句。如：It happened that I was out that day. 碰巧我那天外出了。E.It+doesnt matter (makes no difference,（没有区别） etc.)+连接代词或连接副词引起的主语从句。It doesnt matter whether she will come or not. 她是否来这无关紧要。F. 当主语从句出现在感叹句中时，要以it作形式主语，而把主语从句后置。如：How strange it is that the children are so quiet! 孩子们这么安静真奇怪！He was deeply displeased by what had occurred that day.(介词的宾语从句)注：1如果宾语从句后还有宾语补足语，则用it作形式宾语，而将宾语从句后置。如：We thought it strange that Xiao Wang did not come yesterday.我们认为小王昨天没来是奇怪的。2作介词的宾语：连词that引导的名词性从句作介词的宾语，只用在except, but, in后。其他一些介词的宾语从句