高中英语主语从句

名词性从句之主语从句

名词性从句---- 主语从句

名词性从句之主语从句

Grammar

Subject(主语)

1. You are a student. 2. Smoking is bad for you. 3. To find your way can be a problem. 4. “How do you do?” is a greeting. 5 .What she said is not yet known. 6. That we shall be late is certain. 7. It is certain that we shall be late.

主语的位置上是一个从句，称之为主语从句。

名词性从句之主语从句

主语从句定义：主语从句是在复合句中充当主语的从句，通

常放在主句谓语动词之前或由形式主语 it 代替，而本身放在句子末尾。 引导主语从句的有连词that ,whether,

连 接 代 词 who, what, which, whom, whatever,whoever, whomever, whichever 连接副词when,where, how, why等。

名词性从句之主语从句

1)从属连词：that, whether. that 引导主语从句只起引导作用，本身无实际意义， 在主语从句中不充当任何成分，但不能省略。 whether引导主语从句，本身有实际意义，意为 “是否”,在主语从句中不充当任何成分，不能省 略。That people cut down too many trees destroyed the balance of nature. Whether life will continue on the earth for millions of years will depend on whether this problem can be solved.

名词性从句之主语从句

If × Whether the solid shape would last was not clear. . if It was not clear whether the solid shape would last.真正主语从句 形式主语 引导主语从句在句首只能用whether,

总结

有it作形式主语的whether/if都可以.

名词性从句之主语从句

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, 而把从句放在后面。 例如: 1. That he will refuse this piece of advice is impossible. It is impossible that he will refuse this piece of advice. *it为形式主语 2.That they should like each other is natural.

It is natural that they should like each other.

名词性从句之主语从句

It作形式主语的四种句式结构1) It is + 名词 +真正主语从句 It is a pity 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 common knowledge that… …是常识 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.

名词性从句之主语从句

It作形式主语的四种句式结构 (should) +do…

2) It is + 形容词 +真正的主语从句 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…

It is important that ____________________ we all (should) attend the meeting. (…是重要的)

名词性从句之主语从句

主语从句的虚拟语气①表 “应该，惊讶、惋惜、遗憾”等意义

It is important / natural / necessary/ impossible/ strange + that从句(真正主语从句) 谓语形式为: should + V.原形 , should可省略。 eg. 很奇怪，他竟没有来。

he should not come It is strange that___________________.重要的是我们应该做足够的运动 It i

s important that we should do enough sports.

名词性从句之主语从句

②表示“据建议、据要求、据命令” It + be + suggested/ advised/ ordered/requested/ commanded/ insisted/ required that从句(真正主语从句)

谓语形式:should + V.原形 , should可省略. 据命令，所有乘客必须接受搜查。 It was ordered that ___________________all the(should) be searched passengers___________________________.

名词性从句之主语从句

It作形式主语的四种句式结构 3) It +不及物动词+真正的主语从句 It happened that... 碰巧…… It occurred to me that…我突然想起…

It happened that 刚好)I came into the ________________( office at that time. It occurred to me that 我突然想起)I forget *____________________( to sent the letter.

名词性从句之主语从句

It作形式主语的四种句式结构

4) It + be +过去分词+真正的主语从句 It is said that... 据说…… It is known to all that... 众所周知…… It is reported that... 据报道…… It is believed that...据信……;人们相信…… It is suggested that + (should)do... 建议…… It must be admitted that…必须承认…… It cannot be denied that… 不可否认…… It must be pointed out that…需指出的是……

名词性从句之主语从句

It 作形式主语和it引导强调句的比较 It 作形式主语代替主语从句，主要是为了平 衡句子结构，主语从句的引导词形式多种。 而it引导的强调句则是对句子某一部分进行 强调，无论强调的是什么成分，都可用连词 that。被强调部分指人是也可用who/whom。 例如： It is a pity that you didn’t go to see the film. (it为形式主语) It was yesterday that I bought this bike. (将it was和that去掉，句子仍是完整句子) = I bought this bike yesterday.

名词性从句之主语从句

2.连接代词who ,what ,which, whatever, whichever, whoever

Whoever breaks the law will be punished. Which student will win the first is uncertain. Whatever you did is right. Who the watch belongs to is unknown. What we need is time.

名词性从句之主语从句

3) 连接副词when,where, how, why等。

Why they suddenly disappeared still remains a mystery.When they will set off is not decided. Where she is from is unknown.

How we will paint the house has not been decided.

名词性从句之主语从句

主语从句后的谓语动词一般用单数形式。 Whatever you did is right. Who the watch belongs to is unknown. What we need is time. 注意：若从句的谓语或主句的表语是复数形式， 则谓语动词用复数形式。 What he needs are books. What we need are good doctors.