高中主语从句讲解及其练习
主语从句讲解及练习
主语从句讲解及练习主语从句（一）主语从句的标记主语从句通常由连词that和whether (if)、连接代词或连接副词以及关系代词型what引导。
1. that引导That he is still alive is a wonder. 他还活着，真是奇迹。
That we shall be late is certain. 我们要晚了，这是确定无疑的。
That he should have ignored the working class was natural. 他忽视工人阶级是很自然的。
That she is still alive is a consolation. 她还活着是使人感到宽慰的。
That she became an artist may have been due to her father’s influence. 她成为画家可能是受她父亲的影响。
That you are coming to London is the best news I have heard this long time. 你将来伦敦是好久以来我听到的最好消息。
That she was chosen made a tremendous stir in her village. 她被挑选上，在她村子里引起很大轰动。
2. whether引导Whether it will do us harm remains to be seen. 是否对我们有害还要看一看。
Whether they would support us was a problem. 他们是否会支持我们还是一个问题。
3. 连接代词引导Whoever(=anyone who) fails to see this will make a big blunder. Whatever(=anything that) she did was reasonable. 无论什么Anything that she did was reasonable.Whichever (of you) comes in first will receive a prize. 无论(你们)谁先到都可以得奖。
主语从句超全讲解加练习
主语从句的规律 ：
例4. That whether he will help others is a fact.
正：That he will help others is a fact.
规律四、主语从句中的连词不能重叠使用.
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主语从句的规律 ： 例5. When he will come are a puzzle. 正：When he will come is a puzzle.
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3连接副词when,where, how, why等.
Why they suddenly disappeared still remains a mystery. When they will leave is not decided. Where she is from is unknown. How we will paint the house has not been decided.
规律五、含主语从句的主句谓语动词多用 单数第三人称形式.
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主语从句的规律 ：
1. What he needs is that book.
2. What he needs are some books.
规律六、what 引导的主语从句,可根据 表语决定主句动词的单复数形式.
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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. __I_t _is__im__p_o_s_s_i_b_le__th_a_t_h__e_w_i_ll_r_e_f_u_s_e_t_h_i_s_p_i_e_c_e __o_f_a_d_v_i_c_e_._____________________________
主语从句超全讲解加练习
误:ＩfMaryrｅａllyｈｅaｒdhimis reallyｄoubｔｆul.
正: Wｈｅｔｈer Marｙrｅaｌlyheａrdhｉｍｉsｒｅａlly dｏubtful.
Cｏmpｌeｔetheｓｅntｅnｃｅs usｉng whａt, wheｔhｅr,ｗｈere,wheｎ, whｏ,ｗｈｙ, hｏwｏr tｈａt.
Wｈｅnｔhey wｉlllｅａvｅiｓ ｎoｔｄecided.
Howwewillpaint thehousｅhasnｏｔbeｅｎdecｉdeｄ.
注意:
1)主语从句在句首时，必须由连接词引导,不能省略这些连接词
误:Ｔｈey should lｉｋe eaｃh other isｎatｕrａl.
正：Ｔhａt thｅyshｏuld like each othｅrｉsnａtuｒal
(Who, whom，wｈicｈ，wｈat可以和ever构成合成词,和wｈat一样引导从句，ｅｖer起到强调作用。它们在句子中担任主干成分，并用陈述句形式)
What mａnｙ ｓcｉentiｓｔsｂｅlieve istｈaｔtｈe eartｈiｓrｏunｄ…
Whoｗｉｌl taｋｅpaｒｔin theｍeeting haｓｎoｔbｅen deｃidｅｄ.
Ｉt iｓobｖiｏus thａｔ…很明显…
Iｔ ｉs necｅssary＼ｉｍｐｏrtaｎｔ\natuｒaｌ\..．tｈat…+(sｈｏulｄ)do
_＿__＿_＿_＿__＿＿__＿（很可能）shｅwillcｏme bacｋtomorrow.
*＿__＿＿_＿__＿_____＿＿(很明显)ｔhiｓmeａsurｅiｓeffectiｖｅ.
主语从句讲解及练习
主语从句一.概念：主语从句、表语从句、宾语从句和同位语从句在复合句中的作用相当于名词，因此这四种从句被称为名词性从句。
①主语从句名词性从句共有四种: ②表语从句③宾语从句④同位语从句我们先看几个句子：是谁开始先出招没什么大不了Who takes the first step is not a big deal.…这就是你要离开的原因That’s why you go away....告诉我今夜你想要梦什么Tell me what you want to dream of tonight.最后你会发现每个爱情都危险这个事实Finally you’ll find out the fact that every love is dangerous一．名词性从句的连词连接词：that，if/whether(是否)连接代词：what（+ever）, who(+ever), whom(+ever) , which(+ever), whose连接副词：when, where, how, why, whenever, wherever, however二、主语从句的连词分三类（1）从属连词引导的主语从句（that whether if）that引导的主语从句:引导词that无含义/在句中不做成分/不可以省。
That 引导主语从句通常用it 作形式主语。
例如：That you will win the medal seems unlikely.That you are so indifferent bothers（使…恼怒）me.That she survived the accident is a miracle.（奇迹）whether 引导的主语从句: whether有含义(是否)/在句中不做成分/不可以省。
注意：引导主语从句，在开头不能用if，只能用whether。
Whether we will hold a party in the open air tomorrow depends on the weather.Whether she is coming or not doesn’t matter too much.It’s uncertain whether/if he will come. {不是在句首}（2）用连接代词引导的主语从句在由连接代词what（+ever）, who(+ever), whom(+ever) , which(+ever), whose引导的名词性从句中，其连接代词在句中起名词性作用，担当一定成分.例如：What you need is more practice.What I want to know is this.Whatever we do is to serve the people.注：whatever / whoever的功用whatever, whoever在主语从句中不含疑问意义。
高中英语公开课主语从句讲解练习及答案
主语从句一、主语从句的连词分三类（1）从属连词引导的主语从句（that whether if）that引导的主语从句:引导词that无含义/在句中不做成分/不可以省。
That 引导主语从句通常用it 作形式主语。
That she survived the accident is a miracle.whether有含义(是否)/在句中不做成分/不可以省。
注意：引导主语从句，不能用if不能在开头，只能用whether。
Whether she is coming or not doesn’t matter too much.（2）用连接代词引导的主语从句在由连接代词who, whose, whom, which, what, whoever, whomever, whichever, whatever引导的名词性从句中，其连接代词在句中起名词性作用，担当一定成分.例如Whatever we do is to serve the people.注：whatever / whoever的功用whatever = anything that; whoever = anyone who。
要注意和whatever, whoever 引导的让步状语从句的区别。
如：Whoever breaks the law should be punished. （主语从句）（＝Anyone who breaks the law should be punished. ）Whoever breaks the law, he should be punished. （让步状语从句）（＝No matter who breaks the law, he should be punished. ）（3）用连接副词when, where, why, how引导的名词性从句(其连接副词有含义,在句中作状语。
)例如:Where we should leave it is a problem.When they will come hasn’t been made pubic.三、it 作形式主语的主语从句有时为了考虑句子平衡，通常在主语从句处使用形式主语it，而将真正的主语从句移至句末。
高中英语公开课主语从句讲解练习及解析
高中英语公开课主语从句讲解练习及解析一、主语从句的连词分三类（1）从属连词引导的主语从句（that whether if）that引导的主语从句:引导词that无含义/在句中不做成分/不能够省。
Th at 引导主语从句通常用it 作形式主语。
That she survived the accident is a miracle.whether有含义(是否)/在句中不做成分/不能够省。
注意：引导主语从句，不能用if不能在开头，只能用whether。
Whether she is coming or not doesn’t matter too much.（2）用连接代词引导的主语从句在由连接代词who, whose, whom, which, what, whoever, whomever, whichever, whatever引导的名词性从句中，其连接代词在句中起名词性作用，担当一定成分.例如Whatever we do is to serve the people.注：whatever / whoever的功用whatever = anything that; whoever = anyone who。
要注意和whatever, whoever引导的让步状语从句的区别。
如：Whoever breaks the law should be punished. （主语从句）（＝Anyone who breaks the law should be punished. ）Whoever breaks the law, he should be punished. （让步状语从句）（＝No matter who breaks the law, he should be punished. ）（3）用连接副词when, where, why, how引导的名词性从句(其连接副词有含义,在句中作状语。
)例如:Where we should leave it is a problem.When they will come hasn’t been made pubic.三、it 作形式主语的主语从句有时为了考虑句子平稳，通常在主语从句处使用形式主语it，而将真正的主语从句移至句末。
高中英语公开课主语从句讲解练习及答案
高中英语公开课主语从句讲解练习及答案一、主语从句的连词分三类〔1〕附属连词引导的主语从句〔that whether if〕that引导的主语从句:引导词that无含义/在句中不做成分/不可以省。
That 引导主语从句通常用it 作方式主语。
That she survived the accident is a miracle.whether有含义(能否)/在句中不做成分/不可以省。
留意：引导主语从句，不能用if不能在扫尾，只能用whether。
Whether she is coming or not doesn’t matter too much.〔2〕用衔接代词引导的主语从句在由衔接代词who, whose, whom, which, what, whoever, whomever, whichever, whatever引导的名词性从句中，其衔接代词在句中起名词性作用，担当一定成分.例如Whatever we do is to serve the people.注：whatever / whoever的功用whatever = anything that; whoever = anyone who。
要留意和whatever, whoever 引导的退让状语从句的区别。
如：Whoever breaks the law should be punished. 〔主语从句〕〔＝Anyone who breaks the law should be punished. 〕Whoever breaks the law, he should be punished. 〔退让状语从句〕〔＝No matter who breaks the law, he should be punished. 〕〔3〕用衔接副词when, where, why, how引导的名词性从句(其衔接副词有含义,在句中作状语。
)例如:Where we should leave it is a problem.When they will come hasn’t been made pubic.三、it 作方式主语的主语从句有时为了思索句子平衡，通常在主语从句处运用方式主语it，而将真正的主语从句移至句末。
主语从句讲解和练习题
高考英语主语从句定义：用作主语的从句叫主语从句，它是名词性从句之一。
主语从句的时态：不受主句的时态影响和限制。
引导主语从句的连接词有：从属连词: that, whether；连接代词: who (whoever), whom, whose, what (whatever)和which (whichever)；连接副词: when, where, how和why。
连接词：1. 从属连词：that，whether1）that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，that本身无实际意义，但不能省略。
2）whether意为“是否”，放在句首句末皆可。
由whether引导的名词从句做主语，表语，介词宾语，同位语时！不可用if代替。
a.That price will go up is certain.b. Whether they would support us was a problem. 他们是否会支持我们还是一个问题。
2. 连接代词who ，what ，which, whatever, whichever, whoever (Who, whom, which, what 可以和ever构成合成词，和what一样引导从句，ever起到强调作用。
此类主语从句不能用形式主语it引导，它们在句子中担任成分，不能省略，语序为陈述语序，既有疑问含义,又起连接作用,同时在从句中充当各种成分。
Which side will win is not clear. Whoever breaks the law will be punished.Whatever he did is right. Who killed the scientist remains a question.1）What和that引导的主语从句的区别：that 只起引导作用，不充当任何成分，没有意思。
What 不仅起引导作用，还要充当一定成分(主语、宾语或表语)，意思是：“什么”。
主语从句讲解及练习
主语从句一、名词性从句概述：在句子中起名词作用的句子叫名词性从句(Noun Clauses）。
名词性从句的功能相当于名词词组, 它在复合句中能担任主语、宾语、表语、同位语、介词宾语等，因此根据它在句中不同的语法功能，名词从句又可分别称为主语从句、宾语从句、表语从句和同位语从句。
名词性从句的连词连接词：that，if/whether(是否)，连接代词：what, whatever, who, whoever, whom, whomever, whose, which, whichever连接副词：when, where, how, why, whenever, wherever, however辨别下列名词性从句的类别：1.How the book will sell depends on its author.2.John said that he was leaving for London on Wednesday.3.The fact is that he has not been seen recently.4.The fact that he has not been seen recently disturbs everyone in his office.5.He will talk to us about what he saw in U.S.6.It is impossible that I go and attend the meeting.二、主语从句的连词分三类（1）从属连词引导的主语从句（that whether if）that引导的主语从句:引导词that无含义/在句中不做成分/不可以省。
That 引导主语从句通常用it 作形式主语。
例如：That you will win the medal seems unlikely.That you are so indifferent bothers me.That she survived the accident is a miracle.whether 引导的主语从句: whether有含义(是否)/在句中不做成分/不可以省。
主语从句详解及练习_附答案
高二年级语法要点剖析（李翌洋）一、名词性从句主语从句、表语从句、宾语从句、同位语从句，在整个句子中所起的作用，相当于一个名词。
因此，这四种从句通称为名词性从句。
引导名词性从句的连接词可分为三类：连接词：that, whether, if （不充当从句的任何成分）连接代词：what, whatever, who, whoever, whom, whose, which.连接副词：when, where, how, why1. 主语从句作句子主语的从句叫主语从句。
主语从句通常由从属连词that，whether，if 和连接代词what，who，which，whatever，whoever以及连接副词how，when，where，why等词引导。
that在句中无词义，只起连接作用；连接代词和连接副词在句中既保留自己的疑问含义、又起连接作用，在从句中充当从句的成分。
例如：（1）What he wants to tell us is not clear. 他要跟我们说什么，还不清楚。
It is known to us how he became a writer. 我们都知道他是如何成为一名作家的。
Where the English evening will be held has not yet been announced.英语晚会将在哪里举行，还没有宣布。
注意：有时为避免句子头重脚轻，常用形式主语it代替主语从句作形式主语放于句首，而把主语从句置于句末。
主语从句后的谓语动词一般用单数形式。
常用句型如下：（1）It + be + 名词+ that从句（2）It + be + 形容词+ that从句（3）It + be + 动词的过去分词+ that从句（4）It + 不及物动词+ that 从句另注意在主语从句中用来表示惊奇、不相信、惋惜、理应如此等语气时，谓语动词要用虚拟语气“(should) +do”，常用的句型有：It is necessary (important, natural, strange, etc.) that …It is a pity (a shame, no wonder, etc.) that…It is suggested (requested, proposed, desired, etc.) that…2. 宾语从句名词句用作宾语的从句叫宾语从句。
主语从句超全讲解加练习
It is reported that 据报道)20 people were *___________________( killed in the accident. It is suggested that 建议)we should eat *______________________( more vegetable and do more exercise.
What many scientists believe is that the earth is round … Who will take part in the meeting has not been decided. Whoever breaks the law will be punished.
4.(______ Who can join in the sport meet) is decided by the teach 5.(________ Whether it will rain or not) is not clear.
Conclusion: 主语从句作主语时，谓语动词一般用单数形式。
1. That he will refuse this piece of advice is impossible. It is impossible that he will refuse this piece _______________________________________ of advice. _______________________________________
C That
D Where
3. It
worried her a bit ___ her hair was turning gray. B. that
主语从句讲解和练习题
主语从句讲解和练习题公司内部编号：（GOOD-TMMT-MMUT-UUPTY-UUYY-DTTI-高考英语主语从句定义：用作主语的从句叫主语从句，它是名词性从句之一。
主语从句的时态：不受主句的时态影响和限制。
引导主语从句的连接词有：从属连词: that, whether；连接代词: who (whoever), whom, whose, what (whatever)和which (whichever)；连接副词: when, where, how和why。
连接词：1. 从属连词：that， whether1）that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，that本身无实际意义，但不能省略。
2）whether意为“是否”，放在句首句末皆可。
由whether引导的名词从句做主语，表语，介词宾语，同位语时！不可用if代替。
price will go up is certain.b. Whether they would support us was a problem. 他们是否会支持我们还是一个问题。
2. 连接代词who ，what ，which, whatever, whichever, whoever (Who, whom, which, what可以和ever构成合成词，和what一样引导从句，ever起到强调作用。
此类主语从句不能用形式主语it引导，它们在句子中担任成分，不能省略，语序为陈述语序，既有疑问含义,又起连接作用,同时在从句中充当各种成分。
Which side will win is not clear. Whoever breaks the law will be punished.Whatever he did is right. Who killed the scientist remains a question. 1）What和that引导的主语从句的区别：that 只起引导作用，不充当任何成分，没有意思。
高中英语 主语从句精讲及巩固提升练习(有答案)
主语从句精讲及巩固提升练习概念：从句在整个主句中作主语，因此被称为主语从句。
主语从句隶属名词性从句。
引导词：主语从句引导词分为三类: 连词 that /whether连接代词what / who /whom/which连接副词 when / where/ why /how①连词:that whetherthat：不同于其它的连词，它不充当句子的成分，无意义，不可以省略。
从句句置于句首时，that绝对不可以省略。
（区别于宾语从句）eg. That price will go up is certain.That he finished writing the composition in such a short time surprised us all.Whether “是否”（区别于宾语从句中的if/whether）eg. Whether we go by train or by boat makes no difference.Whether he’ll come here isn’t clear.②连接代词: what who whom whichwhat当what引导主语从句作主语时，指物，谓语动词一般用第三人称单数，下面这个句型例外。
eg. What we need is more time and money.What we need are many more books.who/whom当who引导主语从句作主语时，指代某人。
在从句中作主语不能省略。
翻译是不能把它译成疑问句。
eg. Who will write the poem has not been decided yet.Who will go is not important.③连接副词: where when how whyWhere 表“地点” eg. Where to meet him is still not decided yet.When 表“时间” eg. When he will be back depends on the weather.Why 表“原因” eg. Why he did it remains a mystery.How 表“方式”eg. How the pyramids were built is still a mystery.专项练习（一）1. _______ she couldn't understand was fewer students showed interest in her lessons.A. What... whyB. That. . . whatC. What.. . becauseD.Why.. . thatA. whileB. thatC. ifD. foratmosphere today.A. thatB. whenC. whatD.how4. ______ man first made use of electricity is not exactly known.A. WhenB. IfC. ThatD.What5. _______ we will have a meeting hasn't been decided yet.A. IfB. ThatC. WhatD.WhetherA. That... thatB. What... whatC. Whatever.. . thatD.As... as7. ______ leaves last turns off the light.A. WhoB. WhoeverC. No matter whoD.Whomever8. ______ wins the prize may get the car.A. WhoB. WhomC. WhomeverD.Whoever9. ______ a pity that I didn't see you last week.A. That'sB. What'sC. It'sD.There's10. _______ she will come is certain.A. ThatB. WhatC. /D.WhetherA. If... doB. That... doC. That... doesD.If... does12. ______ has questions can ask the teacher after class.A. WhoB. WhoeverC. AnybodyD.One13. is one of the most useful and fascinating divisions of human knowledge is widely accepted.A. Where chemistryB. That chemistryC. What chemistryD. ChemistryA. whyB. thatC. whetherD.how15.Does _________ matter if he can't finish the job on time?A. thisB. thatC. heD. itA. That... producingB. That... produceC. This... producingD. This... produces17.After Yang Liwei succeeded in circling the earth, our astronauts desire to do is to walk in space.A. whereB. whatC. thatD.how18.It is doubtful________ he knows it or not.A. thatB. ifC. whatD.whether19. _______ caused the accident is still a complete mystery.A. WhatB. ThatC. HowD.Where20. _______ they will hold a sports meeting next week hasn't been decided yet.A. IfB. ThatC. WhatD.Whether21.It doesn't matter________ will take charge of the work.A. whoB. whoeverC. whomD.whomever22._______ is worth doing at all is worth doing well.A. ThatB. WhichC. WhateverD.ItA. What... isB. Whether. .. areC. That... isD.If... is24. _______ some mammals came to live in the sea is not known.A. ThatB. SinceC. AlthoughD.HowA. That... whether... /B. What... if... thatC. That... if... whatD. What. .. whether... /Keys: 1-5 ABCAD 6-10 BBDCA 11-15 CBBBD16-20 BBDAD 21-25 ACCDD专项练习（二）【翻译】1. 新政策会给我们带来好处还是危害还得拭目以待。
高中主语从句解析和例题
1.You know that my flat is opposite to this building.
Object Clause
2. That my flat is opposite to this building is known to
you all.
Subject Clause
3. It is known to you all that my flat is opposite to this
building.
Subject Clause
4. I am worried about whether you can find my flat.
That/what---定从、名从 1）What he said is true.
=____T_h__e_t_h_in_g__t_h_a_t _h_e_s_a_i_d_i_s_t_r_u_e_._____ 2）He is not what he used to be.
= __He__is_n_o_t _th_e_k_in_d_o_f_p_er_s_o_n_th_a_t _h_e _u_se_d__to__be_.__ 3） I know what you need. ___W_h_a_t=_a_ll t_h_at____ 4） What he chose made us very excited.
4.This is _w_h_a_t_ we want to know. 5.Is _w__h_a_t he told us true ? 6.We should pay attention to _w__h_a_t_ the teacher is
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主语从句一、主语从句的连词分三类（1）从属连词引导的主语从句（that whether if）that引导的主语从句:引导词that无含义/在句中不做成分/不可以省。
That 引导主语从句通常用it 作形式主语。
例如：That you will win the medal seems unlikely.That she survived the accident is a miracle.whether 引导的主语从句: whether有含义(是否)/在句中不做成分/不可以省。
注意：引导主语从句，不能用if不能在开头，只能用whether。
Whether we will hold a party in the open air tomorrow depends on the weather.Whether she is coming or not doesn’t matter too much.（2）用连接代词引导的主语从句在由连接代词who, whose, whom, which, what, whoever, whomever, whichever, whatever引导的名词性从句中，其连接代词在句中起名词性作用，担当一定成分.例如：What you need is more practice.Whatever we do is to serve the people.注：whatever / whoever的功用whatever, whoever在主语从句中不含疑问意义。
它引导主语从句，并在从句中作主语、宾语、表语等。
whatever = anything that; whoever = anyone who。
要注意和whatever, whoever引导的让步状语从句的区别。
如：Whoever breaks the law should be punished. （主语从句）（＝Anyone who breaks the law should be punished. ）Whoever breaks the law, he should be punished. （让步状语从句）（＝No matter who breaks the law, he should be punished. ）（3）用连接副词when, where, why, how引导的名词性从句(其连接副词有含义,在句中作状语。
)例如:Where we should leave it is a problem.When they will come hasn’t been made pubic.三、it 作形式主语的主语从句有时为了考虑句子平衡，通常在主语从句处使用形式主语it，而将真正的主语从句移至句末。
这分四种情况：(1)对于以连词that引导的主语从句，通常用形式主语it替代主语从句：<a> It is +名词+从句It is a fact that…事实是……；It is good news that ………是好消息；It is a question that ………是个问题；It is common knowledge that ………是常识类似的名词还有：a pity；a wonder；a good thing；no wonder；surprise等。
It is a mystery to me how it all happened.It is common knowledge that the whale is not a fish.It is no surprise that Bob should have won the game.<b> It is +形容词+从句It is necessary that …有必要……；It is clear that …很清楚……；It is likely that …很可能……；It is important that …重要的是……类似的形容词还有：strange; natural; obvious; true; good; wonderful; possible; unlikely; quite; unusual; certain; evident; worth-while; surprising; interesting; astonishing, etc.It is doubtful whether she will be able to come.It is essential that he should be here by the weekend.It seems obvious that we can not go on like this.It is necessary that you （should）master the computer.需要注意的是这类主语从句中，谓语动词很多为“（should）＋动词原形”，即要用虚拟语气。
<c> It is +过去分词+从句It is said that …据说……；It is reported that …据报道……；It has been proved that …已证明……；It must be proved that…必须指出……类似的过去分词还有：known; estimated; expected; believed; thought; hoped; noted; discussed; required; decided; suggested; demanded; made clear; found out,etc.例如：It is used to be thought that a new star must be due to a collision between two stars.It has not been made clear when the new road is to be opened to traffic.<d> It seems不及物动词（happened / appears / doesn’t’t matter / makes no difference / occurred …）that …主语从句不可提前It makes no difference whether he will attend the meeting or not.It does not matter if I missed my train.It happened that I saw him yesterday.(2)对于以连接代词(副词)引导的主语从句，可以使用形式主语代主语从句，也可直接在句首使用主语从句：Whether they would support us was a problem. 他们是否会支持我们还是一个问题。
It was a problem whether they would support us.他们是否会支持我们还是一个问题。
(3)对关系代词型what引导的主语从句，通常直接将主语从句放在句首。
如：What we need is money. 我们需要的是钱。
What I want to know is this. 我想知道的就是这一点。
有时也可将助用形式主语。
如：It is clear enough what he meant. 他是什么意思很清楚。
(4)如果句子是疑问句，则必须用带形式主语it的结构：Is it true that he is the girl’s father? 他是那女孩的父亲，是真的吗？How is it that you are late again? 你怎么又迟到了？四、连词that的省略问题引导主语从句的连词that 有时可省，有时不能省，其原则是：若that引导的主语从句直接位于句首，则that不能省略；若that引导的主语从句位于句末，而在句首使用了形式主语it，则that可以省略：That you didn’t go to the talk was a pity. 很遗憾你没去听报告。
(that不可省)It was a pity (that) you didn’t go to the talk. 很遗憾你没去听报告。
(that可省)五、六、七、八、九、十、十一、十二、主语从句练习题1、It never occurred to me___you could succeed in persuading him to change his mind.(陕西高考)A．which B．what C．that D．if2、It's obvious to the students________they should get well prepared for their future.(天津卷)A．as B．that C．which D．whether3、________some people regard as a drawback is seen as a plug by many others.(2010·北京)A．Whether B．What C．That D．How4、It is uncertain________side effect the medicine will bring about，although about two thousand patients have taken it.(2010·浙江)A．that B．how C．what D．whether主语从句练习题1.________ makes mistakes must correct them.A. WhatB. ThatC. WhoeverD. Whatever2. It worried her a bit ____ her hair was turning grey.A. whileB. thatC. ifD. for3.When and why he came here ________ yet.A. is not knownB. are not knownC. has not knownD. have not known4. ________ is no reason for dismissing her.A. Because she was a few minutes lateB. Owing to a few minutes lateC. The fact that she was a few minutes lateD. Being a few minutes late5. ________ Tom liked to eat was different from ________.A. That…that you had expectedB. What …that you had expectedC. That…what you had expectedD. What…what you had expected6.________ we go swimming every day ________ us a lot of good.A. If...doB. That...doC. If...doesD. That...does7.It ________ Bob drives badly.A. thinks thatB. is thought whatC. thought thatD. is thought that8.It's uncertain ________ the experiment is worth doing.A. ifB. thatC. whetherD. How9.________ the boy didn't take medicine made his mother angry.A. ThatB. WhatC. HowD. Which10.____ we can't get seems better than ____ we have.A. What, whatB. What, thatC. That, thatD. That, what11.____ you don't like him is none of my business.A. WhatB. WhoC. ThatD. Whether12..____ we'll go camping tomorrow depends on the weather.A. IfB. WhetherC. ThatD. Where13._________is going to do the job will be decided by the Party committee.A. ThatB. WhyC. HowD. Who14._______we'll finish translating the book depends on the time.A. WhenB. WhyC. WhatD. That15.______he won't go there is clear to all of us.A. HowB. WhatC. WhyD. This16.______the house will be built will be discussed at tomorrow's meeting.A. IfB. WhereC. ThatD. What17. ._______you come or not is up to you.A. WhatB. IfC. WhyD. Whether18.._______makes mistakes must correct them.A. WhoB. AnyoneC. WhoeverD. Anybody19.._______team will win the match is a matter of public concern.A. WhichB. ThatC. IfD. How20..________leaves the room last ought to turn off the lights.A. AnyoneB. The personC. WhoeverD. Who。