主语从句语法总结

1、精选优质文档-倾情为你奉上主语从句知识点总结：一，主语从句的定义：在句中充当主语的从句。二，主语从句的引导词： 从属连词：that引导作用，无实际意义，不充当成分，但不能省略whether引导作用，有意义表“是否”，不充当成分，但不能省略连接代词：连接词词义句子中的成分区别连接代词WhatWhoWhom/宾which所.东西谁谁哪个主语，宾语，表语，定语含有疑问含义WhateverWhoeverWhomever/宾whichever无论什么无论谁无论谁无论哪个/些主语，宾语，表语，定语强调一切情况，无疑问含义连接副词：连接词词义在句中的成分连接副词WhenWhereWhyhow.的时间.的地点

2、.的原因.的方式时间状语地点状语原因状语方式状语注意：由that 引导的主语从句，有时为了使句子结构平衡，避免“头重脚轻”，常用it作形式主语，而把从句放后面。例：That students should hard work is necessary.改为it作形式主语：It is necessary that students should hard work.构成一些常用句型：1）It is + n.（名词）+从句It is a pity/shame that. 遗憾的是.It is a surprise that. 令人惊奇的是.It is a fact that. .是事实It is

3、common knowledge that. .是常识例句：It is a pity that(很遗憾)we lost the match.It is a fact that(这是事实）he cheated in the exam.2) It is + adj.（形容词）+从句It's certain that. 肯定.It is possible that. 很可能.It is unlikely that. 不可能.It is obvious that. 很明显.It is necessary important natural.that.+(should) +do.例句：It is

4、 possible that （很可能）she will come back tomorrow.It is obvious that (很明显)this measure is effective.3）lt+ be + 动词的过去分词+ that从句4）lt+ be + 不及物动词+ that从句三，主语从句的用法规则：规则一：主语从句中使用陈述语序。即主语在前，谓语在后。例：When he will come is not known.规则二：主语从句中是主谓一致关系，谓语动词用单数，取决于所跟的表语。例：What I want is water.What I want are apples.规则三：That 在主语从句中不能省略。规则四：引导主语从句在句首只能用whether，有it作形式主语的whether/if都可以.四，主语从句 -学法指导依据“缺什么补什么”原则确定正确的连词。所谓“缺什么补什么”是指从句与连词之间关系。如果句子中缺主语，指人用who，指物用what；如缺宾语，指人用whom，指物用what;如缺时间状语用when; 地点状语用