主语从句(精讲精练)

主语从句
一．主语从句的结构：主语从句+ 谓语动词+ （宾语）+ 状语或其他
That he failed the math exam surprised all of us.
That you joined us made all of us happy.
That he didn’t care for money was a lie.
Whether we’ll go out for an outing depends on the weather.
What he did added to our difficulty.
What surprised everybody was that he didn’t come to the meeting.
二、主语从句的词有从属连词、连接代词、连接副词。

从属连词：that，whether
1.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。

That he will win is certain.
That the earth travels around the sun is a well-known fact.
●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。

That he will win is certain.
=It is certain that he will win.
That the earth travels around the sun is a well-known fact.
=it is a a well-known fact that the earth travels around the sun
2.whether引导主语从句只起引导作用，在主语从句中不充当任何成分,意思为“是否”
Whether he’ll come here isn’t clear. 他是否会来这里还不清楚。

Whether you can do it by yourself mainly deoends on your ability,not your age.
Whether she is coming or not doesn’t matter.
连接代词：who,whom,whose,which,what,whoever,whatever,whichever
表疑问：who 谁，作主语，宾语，表语
whom 谁，作宾语
whose 谁的作定语
which 哪一个作定语，主语，宾语，表语
what 什么作主语，宾语，表语
Who she is doesn’t concern me.
Who you are looking for is not known to us.
Who can do such work is not easy to know.
Which team will win is uncertain.
Which should be chosen remains uncertain.
Whose watch was lost is unknown.
What had happened is still a mystery.
表陈述：what 所---的人/物/样子/地方等作主语，宾语，表语
What he wants is a new bicycle.
What I want to know is this.
What he says is not important.
What I am afraid of is their taking him to Portugal.
What you need is a good-sized canvas bag.
What really matters is that she wore a pair of white shoes.
What is known is that the 2008 Olympic Games will take place in Beijing.
●whatever .whoever .whichever.whomever表陈述，作主语、宾语、表语等,
Whoever(Anyone who) wants to enter into this school must take the exam.
Whoever told you that was lying.
Whatever(Anything that) she did was right.
Whatever was said here must be kept secret.
Whichever you want is yours．
连接副词：where,how,why,when （状语）
When we arrive doesn’t matter. 什么时候到没有关系。

How this happended is not clear to anyone. 这件事怎样发生的，谁也不清楚。

Where I spend my summer holiday is no business of yours.
How many people we are to invite is still a question. 邀请多少人还是一个问题。

三、形式主语it构成的主语从句
It + be + 名词+ that从句（a pity, a shame, a fact, an honour, a wonder, a good thing, no wonder等。

）
惯用句型有：
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 is no wonder that …难怪……
It is a pity that …真遗憾
It is a pity that she has made such a mistake.真遗憾，她犯了这样一个错误。

It is no wonder that he has passed the examination.难怪他考试及格了。

It is a shame that you have to leave so soon.你必须这么早离开，真遗憾。

It was a stupid thing that he didn’t listen to his teacher.他不听老师的话，真蠢。

It is a great honour that he receive that prize.他得到了那个奖真是无上的荣耀。

It is a fact that he cheated in the exam.
It + be +形容词+ that从句…
用于该句型中的形容词有：clear, obvious, true, certain, important, strange, natural, surprising, fortunate, good, wonderful, funny, possible, impossible, likely, unlikely, quite clear, unusual等。

惯用句型有：
It is necessary that…有必要……
It is important that…重要的是……
It is obvious that…很明显……
It is likely that…有可能……
It is important that we (should) learn English well.我们学好英语是非常重要的。

It is necessary that the students (should) remember all the new words.学生记住所有的新单词是必要的。

It + be + -ed 分词+ that从句
常见的过去分词有：said, reported, learned, announced, known, decided, expected, believed, considered, declared, felt, hoped, seen, supposed, thought, understood等。

惯用句型有：
It is said that…据说
It is reported that…据报道
It is believed that…大家相信
It is hoped that…大家希望
It is well known that…众所周知
It is thought that…大家认为
It is suggested that…据建议
It has been decided that…大家决定
It must be remembered that…务必记住的是
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……
It is reported that another man-made satellite has been put into orbit.据报道又一颗人造卫星送入轨道。

It is said that he has gone to the USA for further study.据说他已去美国深造了。

It is known to all that light travels in straight lines.众所周知，光以直线运行。

It has been decided that we should design the machine ourselves.已经决定我们自己来设计这部机器。

It + 及物动词+ 名词+ 从句
It makes no difference to me whether it’s foggy or clear.对我来说，天气有雾或晴朗没什么关系。

It + 不及物动词+ that分句
常见的不及物动词有：seem, happen, look, appear, come about, turn out, occur等。

惯用句型有：
It appears that…似乎……
It (so) happens (that)…（那么）碰巧……
It occurred to me that…我突然想起……
It seems that …似乎……
It doesn’t matter (to sb.) + 从句（对）……都无所谓
It seems that he is sick. (= He seems to be sick.)看来他似乎有病。

It happened that he wasn’t there. (= He happened not to be there.)碰巧他不在哪儿。

It occurred to me that I forgot to send the email.
It doesn’t matter to me what he says.对我来说，他说什么都无所谓。

It doesn’t matter if we are late.我们就是晚到一点也不要紧。

●主语从句的谓语动词的虚拟语气，要用should 加动词原形，should 可省略。

(1) suggested, ordered, proposed, required, demanded, requested, insisted + (should) do
(2) important, necessary, natural, strange + (should) do
(3) a pity, a shame, no wonder + (should) do
It is suggested that we (should) hold a meeting next week.
It is necessary that he (should) come to our meeting tomorrow.
需要注意的是,it作形式主语时,要注意和as引导的定语从句的区别。

试比较:
①It was reported that no country was under the terrorist attack last year.
②As was reported, no country was under the terrorist attack last year.
句意:据报道,去年没有国家遭到恐怖分子的袭击。

四：主谓一致：一般说来，单个的主语从句做主语，主句的谓语动词用单数。

That we go swimming every day does us a lot of good.
练习题
1.________ makes mistakes must correct them.
2. It worried her a bit ____ her hair was turning grey.
3.It's uncertain ________ the experiment is worth doing.
4.________ the boy didn't take medicine made his mother angry.
5.____ we can't get seems better than ____ we have.
6.____ we'll go camping tomorrow depends on the weather.
7._________is going to do the job will be decided by the Party committee.
8.______the house will be built will be discussed at tomorrow's meeting.
8._______team will win the match is a matter of public concern.
10.________leaves the room last ought to turn off the lights.
11.It is obvious to the students ______ they should get well prepared for their future.
12. was most important to her，she told me，was her family.
13. matters most in learning English is enough practice.
14. parents say and do has a life-long effect on their children.
15.It is none of your business other people think about you.Believe yourself.
16. makes this shop different is that it offers more personal services.
17.They lost their way in the forest, and made matters worse was that night began to fall．
18. really matters is not whether you succeed or not，but rather wh ether you’11 try or not．
19.When faced with life and death decisions, a teacher can be expected to do is to protect students
with his or her own life．
20.. is responsible for this accident will be punished．
21. is known to everybody that Taiwan is part of China
22.. is known to us all is that the old writer，for life was hard in the past，still works
very rd in his eighties.
1. __________________________ (他在会上所说的) has nothing to do with you.
2. _______________________ (谁将赢得这场比赛) is still unknown.
3.__________________ was an end to all the armies of the world.(他所希望看到的是）
4. ___________________ remains a question.(谁杀死了这位科学家）
5. ______________________________ is still uncertain. (我们是否能控制洪水）
6. __________________________ is unknown.(车站将于何时竣工）
7. ________________________is what I want to know. (他们是怎样去美国的）
8.他在找什么与你无关。

9.他喜欢这种书，这件事非常有趣。

他是否能来仍然是个问题
10.他们哪一个是从监狱里逃跑的，仍然是个谜。

11.飞机何时起飞还没有宣布。