名词性从句解析

名词性从句解析 名词性从句相当于名词，可分别作主句的主语、表语、宾语和同位语。因此，名词性从句分为主语从句、表语从句、宾语从句和同位从句。名词性从句,顾名思义,它具有名词性.所以可以作主语,宾语等等.回忆一下句子成分那一章（一）引导名词性从句的连接词1、连接代词：who, whose, whom, what, which。有词义，在从句中担任成分，如主语、表语、宾语、或定语等。2、连接副词：when, where, why, how。有词义，在从句中担任成分，作状语。3、连接词：that, whether, if, as if, that（二）主语从句1、主语从句在复合句作主语。?Who will go is not important.2、用it作形式主语，主语从句放在句末。?It doesn’t matter so much whether you will come or not.3、that引导主语从句时放在句首时，不能省略。That he suddenly fell ill last week made us surprised.实用例句:Is it true that he will be punished seriously by the headmaster?Does it make any difference who bought these gifts?How strange it is that these children are so quiet!注意: 表示是否,只能使用whether.（三）表语从句1、表语从句在复合句中作表语，位于系动词之后。The question was who could go there.2、引导表语从句的连接词that有时可省去。My idea is (that) we can get more comrades to help in the work.注意: 表示是否,只能使用whether.（四）宾语从句1、宾语从句在复合句中作宾语。引导宾语从句的连词that一般可省略。?I hope (that) everything is all right.2、介词之后的宾语从句，不可用which或if连接，要分别用what或 whether。I’m interested in whether you’ve finished the work..I’m interested in what you’ve said.3、whether与if都可以引导宾语从句，常可互换。但下面情况不能互换。if和whether区别①宾语从句是否定句时，只用if，不用whether。e.g. I wonder if it doesn’t rain.②用if 会引起误解，就要用whether。e.g. Please let me know whether you want to go.（此句如果把whether改成if，容易当成条件句理解）③宾语从句中的whether 与or not直接连用，就不能换成if；不直接连用，可换。e.g. I don’t know whether or not the report is true.I don’t know whether/ if the report is true or not.④介词后的宾语从句要用whether引导。whether 可与不定式连用。whether也可引导主语从句、表语从句、同位语从句，还可引导让步状语从句，以上均不能换成if。但引导条件从句时，只能用if，而不能用whether。It depends on whether we have enough time.They don’t know whether to go there.Please come to see me if you have time. 状语从句实用例句: 使用it作形式宾语I thought it impossible that he could finish this job in just two hours.He left it to my judgment whether we should continue this project.注意: 形式主语和形式宾语只有一个替代词: it （五）同位语从句同位语从句在句中作某一名词的同位语，一般位于该名词（如：news, fact, idea, suggestion, promise等）之后，说明该名词的具体内容。I have no idea when he will be back.The fact that he had not said anything surprised everybody. ... ...