主语从句详细讲解及综合练习

主语从句

一、概念：在复合句中起主语作用的从句叫主语从句。

(一) 连接词

从属连词：that、whether；

关系代词：who, what, which , whom, whose, whatever, whoever, whomever, whichever 关系畐【J词：when, where, how, why, however, whenever, whereve等；例: What he said is true.

That you don' t like him is none of my bus in ess. Whether the football game will be

played depe nds on the weather.

主语从句的时态：不受主句的时态影响和限制。

(1)______ he finished writing the composition in such a short time ______ 惊讶)us all.

(2)_______ ___________________________________ w e will go for an outing tomorrow (remains, remained) unknown.

(3)_______ _____________________ will be our monitor (be) decided yet.

(4)______ we must study for ______ (be) a question of great importanee.

(5)_______ _______________________ caused the accident (remains, remained) unknown.

(6)______ you did _______ (be)right.

(7)______ watch ______ (be) lost is unknown.

(8)______ we need ______ (be) time.

(9)______ we need ______ (be) good doctors.

小结：

(1)主语从句的时态：不受主句的时态影响和限制。

(2)连词位于句首不能省略(3)主语从句大多数情况下视为三单，但也有例外，如例9

1. 从属连词that, whether引导的主语从句。

从属连词that, whether在主语从句中的作用只是引导主语从句，在从句中不担任成分，不能省略。

例: ___________ they will go is certa in.

_________ s he will come or not is still a questi on. she's coming or not does n't matter

too much.

2. it作形式主语引导主语从句。

如果主语从句太长，为避免句子结构头重脚轻，我们可用it作形式主语，而把主语从句放

在主句谓语部分之后。That引导的主语从句可用it代替，that不可省略。

It ' s reported that … 据报道 ... It ' s decided that …尚未决定

It ' s believed that … 据认为 .. It ' s announced that …据宣布 ..

It suddenly struck me (occur to me that … 我突然想至U (感觉至U) .

(5)其他

It doesn' t matter …是无关紧要的

It makes no differe nee …毫无区另

It is of little con seque nee that-无关紧要 It is a pity __________ she has made such a mistake 她犯这样的错误是令人遗憾的事。

It's strange _________ he did n't come yesterday 他 昨天没来是很奇怪的。

It is reported _________ the nu mber of wild ani mals in Africa is decreas ing.

据报导非洲野生动物的数量正在减少。

It is said __________ there was a terrible pla ne crash this morning.

据说今天早上有一起可怕的飞机坠毁事故。

1主语从句在句首时，必须由连注意：

接词引导，不能省略这些连接词；但是如果用 it 做形式主语，而把主语从句放在句末时，从 属连词that 可以省略。

误：They should like each other is natural.

正： That they should like each other is n atural.

正: It is natural that they should like each other.

2)如果主语从句放在句首，不能用if 引导，但是如果用it 做形式主语，而把主语从句放在句 末时，也可以用if 引导.

误：If Mary really heard him is really doubtful.

正: It was doubtful if Mary really heard him.

4) .用于 It is important / natural / necessary / impossible that...句型中,主语从句应使用虚拟语 气谓语动词用 “should +动词原形”的形式,should 有时可以省略。

5) 在 It + be+suggested/advised/ordered/requestedn sisted/required 中，that 从句的谓语也应该 用“should +动词原形”的形式,should 有时可以省略。

Does ______ matter if he can't finish the job on time ?A. this B. that C. he D. it

______ is a fact that En glish is being accepted as an intern ati on al la nguage.

A. There

B. This

C. That

D. It

用作it 作形式主语的结构： (1) It is/was + 形容词 +that 从句 It ' s natural that … 很自然 .... It ' s fortunate that … 幸运的是 It ' s unlikely that …不可能 (2) It is/was + 名词 +that 从句 It ' s a pity that … 遗憾的是 .... It ' s good news that …是好消息… It ' s an honour that … 非常荣幸 It ' s com mon kno wledge that … 是常识… (3) It +不及物动词+that 从句 It seems that … 似乎 ... It appears that-•看来 ... (4) It is/was +过去分词+that 从句

It ' s obvious that …显而易见 It ' s (im)possible …(不)可能… It ' s stra nge that ••奇怪的是 ......

It ' s a fact that …事实是 ... It ' s a wonder that …不足为奇… It ' s a shame that--真是可It happe ned that …碰巧 It turns out that- ••结果…