1、名词性从句,名词性从句的概念,概念：起名词作用的从句叫名词从句。它和名词一样，在句中可充当主语，表语，宾语和同位语。名词从句包括主语从句，表语从句，宾语从句和同位语从句。名词从句的引导词通常有： 1. 连词 that, whether, if. 2. 连接代词what, whatever, who, whoever, whose, which3. 连接副词when, where, how, why,请判断出下列的句子属于哪种从句,What I want to do is taking a bath.The news that they won the game spread the whole
2、 school.I dont think he is an honest boy.The fact is that he stole the car.Do you know the fact that he stole the car?Do you know the man who is standing over there?It is said that they won the game.,(主从),(同位语从句),(宾从),(表从),(同位语从句),(定从),(主从),主语从句,在句中充当主语的从句叫做主语从句。主语从句可以放句首,但多数放句末.句首用形式主语IT.,That the
3、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. 注意：连词that, whether在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。 3. Who let out the news remained unknown. 4. How this happened is still a question.
4、 5. Why he didnt come here is not clear to anyone. 注意：who, which, how, when, where, why在所引导的主语从句中可担任主 语，宾语，状语，不能省略。可以用形式主语it引导。,6. What he said at the meeting is important.,7. Whoever leaves the office should tell me.,8.Whenever the Olympic Games will be held in Beijing is not known yet.,注意：who, who
5、m, 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。,另外，有的“It 主语从句”已成为固定结构。如：,It + is + 形容词 that从句,It is necessary that 有必要It is important that . 重要的是It is obvious that 很明显,It + is + -ed分词 that从句,It is believed that 人们相信It is known to us/all that . 众所周知It has been decided that 已经
6、决定,It + is + 名词 that从句,It is common knowledge that 是常识It is a surprise that . 令人惊奇的是It is a fact that 事实是,It + 不及物动词 that从句,It appears that 似乎It happens that . 碰巧It occurred to me that 我突然想起,表语从句,在句中充当表语的从句(多数放在be动词后面)叫做表语从句。,Thats what we should do.,Our purpose is that he can realize his faults.,注意
7、：引导表语从句的连接词一般不省略。,Thats why I want to see you.,The question is whether it is worth doing,注意：表语从句表示“是否” 只用“whether” 而不用“if”,1. be, seem, look等动词后均可跟表语从句：,My suggestion is that we should go shopping.,It seems that it is going to rain.,2. as if, because 也可引导表语从句。,It looks as if its going to rain.,It wa
8、s because I got up late.,注意：在表语从句中，当reason作主语时，引导词只能用that，不能用because，如： The reason why he was late was that he didnt catch the early bus.,试区分以下句子,Is this museum what you visited?,Is this the museum that you visited?,Is this museum the one that you visited?,注意：这种句子考试时一定要记住这句话：名词前（尤其是单数可数名词前）一定要有限定词。然
9、后把句子变换成陈述句，接着判断句子是属于哪种从句再完成。,(表从),(定从),(定从),宾语从句,在复合句中充当宾语的句子叫做宾语从句。,1.作动词宾语,I dont know （that） you will come here.I wonder what he has done.,2.作介词宾语The teacher is satisfied with what I said.He is thinking about how to solve the problem.3.作afraid,glad,certain,sure等形容词的宾语I am afraid that I will be la
10、teI am glad you passed the exam.,我不知道他来不来。我想知道他来还是不来。你们是在谈论着他来还是不来吗？他不在乎天气是否好。,I dont know whether/if he will come.,I want to know whether he will come or not.,Are you talking about whether he will come?,He doesnt care if it isnt a fine day.,注意：在宾语从句中，表示“是否”既可以用whether,也可以用if.但是，whether常与or not连用；作介
11、词宾语只用whether; 从句是否定句时一般用if。,宾语从句中的否定转移,我认为他不会来这里,I think he wont come here. ( )I dont think he will come here. ( )I believe he wont see you.I dont believe he will see you.,注意：如果宾语从句是由think, believe, imagine, suppose,expect等词引导的时候，要将从句中的否定形式转移到主句中去。,宾语从句中用it作形式宾语,We think it our duty that we should h
12、elp others.I find it impossible that he should finish the work in two days.I consider it necessary that he should do it again.,注意：如果主句中有形容词或名词作宾语补足语时，一般用it来作形式宾语，把从句放在宾补后面。,I insisted that he （should）do it at once. She suggested that the work （should）be finished at once. IThe mayor ordered that the
13、bridge (should) be repaired as soon as possbile.,注意：在suggest, insist, demand, order, require 等表示建议，命令，要求的动词后，从句的谓语动词要用虚拟语气。如：,同位语从句,在句中用作同位语的从句叫做同位语从句。同位语从句一般放在如idea, news, fact, promise, suggestion, belief, hope, thought, doubt,truth等含有丰富内涵的词语后面，用来说明前面那个词的具体内容。一般说来，同位语从句都用that来作连接词，而且不能省略。也可用how, w
14、hen, where等。,他给了她一个承诺，他会在两个月后回来。,He gave her a promise that he would come back after two months.,Some more examples,The rumour that there will be an earthquake soon spread all over the area.2. They have no hope that he will recover. 3.I have no idea where they have gone. 同位语从句与先行名词有时也可以分开: 4.Suddenl
15、y the thought came to me that he could go blind.,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在句中不担任句子成分，而引导定语从句的that则在从句中作主语，宾语等。 （3）同位语从句与先行名词是等同关系，一个具体，一个抽象，两者常可以转述为主表关系，而定语从句与先行词是修饰与被修饰关系。 （）如果是定语从句，它的从句肯定是不完整的，关系词肯定在句中充当成分的；而同位语从句中的that只起连接作用。 （）定语从句是对先行词起修饰作用，而同位语从句则解释说明先行词的具体内容。,试区分以下句子,Do you know the fact that he stole the car?,Do you know the fact that they were talking about?,The news that our team won the game is true. （_） The news that you have heard isnt true. （_）,(同从),(定从),
