完整版主语从句和同位语.docx

1、完整版主语从句和同位语主语从句、主语从句的连词分三类that 引导的主语从句 :引导词 that 无含义 /在句中不做成分 /不可以省。 That 引导主语从句通常用 it 作形式主语。例如： That you will win the medal seems unlikely.That she survived the accident is a miracle.whether 引导的主语从句 : whether 有含义 （是否 ）/在句中不做成分/不可以省略。注意：引导主语从句，不能用 if 不能在开头，只能用 whether。Whether we will hold a party in

2、 the open air tomorrow depends on the weather.Whether she is coming or not doesn mtatter too much.2） 用连接代词引导的主语从句 在 由 连 接 代 词 who, whose, whom, which, what, whoever, whomever, whichever, whatever 引导的名词性从句中，其连接代 词在句中起名词性作用，担当一定成分 例如： What you need is more practice.Whatever we do is to serve the peopl

3、e.注： whatever / whoever 的功用whatever, whoever 在主语从句中不含疑问意义。它引导主语从 句，并在从句中作主语、宾语、表语等。whatever = anything that; whoever = anyone who 。要注意和whatever, whoever 引导的让步状语从句的区别。如： Whoever breaks the law should be punished. (主语从句)( =Anyone who breaks the law should be puni shed.)Whoever breaks the law, he shoul

4、d be punished. (让步状语从 句)( =No matter who breaks the law, he should be puni shed.)3)用连接副词 when, where, why, how 引导的名词性从句 (其连接副词有含义 ,在句中作状语。 )例如 :Where we should leave it is a problem.When they will come hasn bteen made pubic.三、 it 作形式主语的主语从句有时为了考虑句子平衡，通常在主语从句处使用形式主语 it，而将真正的主语从句移至句末。这分四种情况：(1)对于以连词 t

5、hat 引导的主语从句，通常用形式主语 it 替代主 语从句： It is +名词 +从句It is a fact that 事实是 ；It is good news that 是好消息；It is a question that 是个问题；It is com mon knowledgethat 是常识 类似的名词还有： a pity； a wonder； a good thing； no wonder； surp rise 等。It is a mystery to me how it all happened.It is common knowledge that the whale is

6、not a fish.It is no surprise that Bob should have won the game.It is clear that 很清 It is + 形容词 +从句It is necessary that 有必要 楚； It is likely that 很可能； It is important that 重要的是 类似的形容词还有： strange; natural; obvious; true; good; wonderful;possible; unlikely; quite; unusual; certain; evident; worth-while;

7、surprising; interesting; astonishing, etc.It is doubtful whether she will be able to come.It is essential that he should be here by the weekend.It seems obvious that we can not go on like this.It is necessary that you （ should）master the computer.需要注意的是这类主语从句中， 谓语动词很多为 (should) +动 词原形”，即要用虚拟语气。It It

8、 is +过去分词 +从句It is said that 据说； It is reported that 据报道须指出 类似 的 过去分词还有 ： known; estimated; expected; believed;thought; hoped; noted; discussed; required; decided; suggested;demanded; made clear; found out,etc.例如： It is used to be thought that a new star must be due to a collision between two stars.

9、It has not been made clear when the new road is to be openedto traffic. It seems 不及物动词( happened / appears /doesn tt matter / makes no differenee / occurred )that 主语从句不可提前It makes no difference whether he will attend the meeting or not.It does not matter if I missed my train.It happened that I saw h

10、im yesterday.(2)对于以连接代词 (副词 )引导的主语从句， 可以使用形式主语 代主语从句，也可直接在句首使用主语从句：Whether they would support us was a problem. 他们是否会支持我 们还是一个问题。It was a problem whether they would support us. 他们是否会支持我 们还是一个问题。(3)对关系代词型 what 引导的主语从句， 通常直接将主语从句放 在句首。如：What we need is money. 我们需要的是钱。What I want to know is this. 我想知道的

11、就是这一点。有时也可将助用形式主语。如： It is clear enough what he meant.他是什么意思很清楚。(4)如果句子是疑问句，则必须用带形式主语 it 的结构：Is it true that he is the girl s father? 他是那女孩的父亲，是真的 吗？How is it that you are late again? 你怎么又迟到了？ 四、连词 that 的省略问题 引导主语从句的连词 that 有时可省，有时不能省，其原则是： 若 that 引导的主语从句直接位于句首，则 that 不能省略；若 that引导的主语从句位于句末，而在句首使用了形

12、式主语 it ，则 that可以省略：That you didn t go to the talk was a pity. 很遗憾你没去听报告。（that 不可省 ）It was a pity （that） you didn t go to the talk. 很遗憾你没去听报告。（that 可省 ）同位语从句、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

13、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

14、，因此该句为同位语从句。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 o nee.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。引导同位语从句。 （if 不能引导同位语从

15、句）例： Well 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，应力Q 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 、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.合匕析： 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 we nt home意义不完整，应加 ”如何的含义才能表达 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