主语从句讲解
主语从句讲解及习题
名词性从句之主语从句一、名词性从句概述：在句子中起名词作用的各种从句统称为名词性从句。
根据它们在句中的语法作用，这类从句又可分为主语从句、同位语从句、表语从句和宾语从句。
二、主语从句定义：在句中起主语作用的从句称为主语从句。
引导主语从句的连接词主要有：单纯连词(that, whether/ if)、连接代词(what, whatever, who, whoever, whom, whose, which, whichever 等)和连接副词(when, where, why, how, whenever, wherever, however 等)。
1)that引导的主语从句(1)由连词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。
例如：That you will win the medal seems unlikely.你能得奖看起来不大可能。
That light travels in straight lines is known to all.众所周知，光沿直线传播。
That you don’t like him is none of my business.你不喜欢他不管我的事。
(2)形式主语it替代主语从句位于句首，that引导真正的主语从句会放到句子的后面。
常用的句式主要有如下几种：1.It+系动词+形容词+that从句。
如：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.例如：It was really astonishing that he refused to talk to you.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.It is important that a student learn English well.It' s clear that they badly need help.It is likely that a hurricane will arrive soon.知识拓展：在“It is necessary / important/surprising/strange/unthinkable/unbelievable/incredible+that 从句”这类主语从句结构中，从句中谓语动词常用(should) +动词原形”，形式，即要用虚拟语气should 可省略。
主语从句讲解及练习
主语从句讲解及练习什么是主语从句？主语从句是由一个从句充当主语的句子结构，它由连接词引导，用来说明主语的内容或者起到引入主题的作用。
主语从句的引导词一般情况下，主语从句由以下连接词引导：- that- whether/if- who/whom- which- what- whatever- whoever- whichever主语从句的用法主语从句在句子中承担主语的角色，可以帮助我们表达某个动作、状态、事件或者事实的主题。
下面是一些常见的用法示例：1. 表达事实或真理：例如：That he is innocent is beyond doubt.（他的无辜是毫无疑问的。
）2. 表达感觉或观点：例如：What he said is very interesting.（他说的话很有趣。
）3. 引导宾语从句：例如：I believe that he will succeed.（我相信他会成功。
）主语从句的位置一般情况下，主语从句位于句首或者句中，具体位置取决于句子的结构和语境。
主语从句的练题请根据下面的句子，填写合适的主语从句：1. __________ you did yesterday surprised everyone.（你昨天做的事让大家都吃惊。
）2. __________ will happen remains unknown.（将会发生什么还不确定。
）3. __________ is important to study hard.（努力研究是很重要的。
）5. __________ we need is more time.（我们所需要的是更多的时间。
）参考答案：1. What2. What3. It4. Whether/if5. What以上是对主语从句的讲解及练习，希望对你的学习有所帮助。
主语从句详细讲解
it 作形式主语，而把主语从句放It'obvious that -显而易见…It'(im)pIt happened that -碰巧 It turns out that- ••结主语从句 「、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 关系代词 关系副词 that 、whether ；who, what, which , whom, whose, whatever, whoever, whomever, whichever whe n, where, how, why, however, whe never, whereve 等 ；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._____________ she will come or not is still a questi on. shesco ming or not does n't mattertoo 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 在主句谓语部分之后。
用作it 作形式主语的结构：⑴It is/was +形容词+that 从句 It 'natural that … 很自然 ............... It 'fortunate that … 幸运的是 It 'unlikely that …不可能 (2) lt is/was + 名词 +that 从句 It 'a pity that … 遗憾的是 ............. It 'good n ews that …是好消息 .......... It 'an honour that … 非常荣幸 ............ It '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)lt is/was +过去分词+that从句It 'not known that ................ 不得而知It 'said that …据说 ............It 'reported that… 据报道............ It' decided that ••尚未决定It 'believed that… 据认为 ............ It 'ann ou need that…据宣布........It suddenly struck me (occur to me that… 我突然想至U (感觉至U) ........⑸其他It doesn'tmatter… 是无关紧要的It makes no differenee… 毫无区另S ........It is of little con seque nee that …无关紧要［随堂练］It is a pity ______________ she has made such a mistake她犯这样的错误是令人遗憾的事。
初中语法 主语从句讲解及(完整版)
主语从句：即在复杂句中充当主语成分的句子例如"That he finished writing the composition in such a short time surprised us all"，他在很短的时间内写完作文让我们都很惊讶, 此复合句主要描述的是某事让我们惊讶，某事就是该复合句的主语，因此"That he finished writing the composition in such a short time" 便是该复合句的主语从句。
主语从句使用陈述语序，其通常结构为“引导词+ 主语+ 谓语+ 其他成分”；但当连接代词同时充当从句主语时，其结构为“连接代词+ 谓语+ 其他成分”。
时态：主语从句的时态不受主句时态的影响和限制引导主语从句的连词主要有:从属连词:that、whether （只起连接作用，不充当句子成分）连接代词:who、whoever、whom、whose、what 、whatever 、which 、whichever （既有连接作用，又做从句的主语、宾语、表语或定语）连接副词:when、where 、how 、why whenever、wherever（既有连接作用，又做从句的状语）例句：1. that引导例句：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。
2. whether引导例句：Whether they would support us was a problem. 他们是否会支持我们还是一个问题。
3. 连接代词引导例句：Whoever is top from wins the game when two matched players meet. 两强相争勇者胜。
2023年高中英语语法精讲,主语从句详细讲解
2023年高中英语语法精讲—主语从句详细讲解主语从句结构及用法在句子中担当主语的从句就叫做主语从句，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。
通常结构为“引导词 + 主语 + 谓语 + 其他成分"。
一. 概念：在句子中担当主语的从句就叫做主语从句，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。
主语从句使用陈述语序，其通常结构为“引导词 + 主语 + 谓语 + 其他成分", 但当连接代词同时充当从句主语时，其结构为“连接代词 + 谓语 + 其他成分”。
二. 引导词：1. that引导eg. That you are coming to London is the best news I have heard this long time.2. whether引导eg. Whether they would come to conference was a question.3. 连接代词引导: who,whom, whose, what, which, whoever, whomever, whichever, whatevereg. Whoever is top from wins the game when two matched players meet.4. 连接副词引导: therefore, besides, otherwise, however, moreover, still, thus, meanwhileeg. How this happended is not clear to anyone.5. 关系代词型what引导三. 形式主语it:1. 对关系代词型what引导的主语从句，可以使用形式主语。
eg. It is clear enough what he meant.2. 如果句子是疑问句，则必须用带形式主语it的结构.eg. Is it true that all of us need to to conference?如果一个句子在复合句中充当一个主语,那么这个句子就是主语从句。
主语从句讲解
1 / 5主语从句讲解主语从句主语从句定义:在句子中担当主语的是一个从句,这个从句就叫做主语从句。
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。
1.引导主语从句的关联词有三类：(1)从属连词that，whetherThat they were true sisters was clear from the facial resemblance between them.Whether he'll come here isn't clear.(2)连接代词who, whom, whose, what, which, whoever, whatever, whichever，What she did is not yet known.How this happened is not clear to anyone. Whoever comes is welcome. (3)连接副词where，when, how, why2.主语从句是在复合句中充当主语的从句，其功同名词一样。
为了避免头重脚轻，常用it作形式主语,而把真正主语放在句子末尾。
How the book will sell depends on its author. That he is the best student in the class is obvious. = It is obvious that he is the best student in the class. 注意：主语从句不可位于句首的五种情况(1) if引导的主语从句不可居于复合句句首。
(2) It is said , (reported) …结构中的主语从句不可提前。
2 / 5例如：It is said that President Jingo will visit our school next week.(3) It happens…, It occurs…结构中的主语从句不可提前。
主语从句讲解
主语从句讲解• 主语从句• 一、主语从句的引导词• 主语从句通常由连词that和whether/if、连接代词或连接副词引导。
• 1. that引导• 2. whether引导• 3. 连接代词引导• 4. 连接副词引导• 5. 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.1• 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 co ming 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。
• 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• who will give us a talk is unknown at all . • Whichever (of you) comes in first will receive a prize.无论(你们)谁先到都可以得奖。
高中英语主语从句
高中英语主语从句主语从句，在英语语法中，是一个句子作为主语，它可以是陈述句、疑问句或者是特殊疑问句。
这种从句在高考英语中占据了重要的地位，因此，理解和掌握主语从句的用法对于高中生来说至关重要。
我们要理解什么是主语从句。
主语从句就是一个句子在复合句中充当主语，例如：What he said is not true.在这个句子中，“What he said”就是一个主语从句。
主语从句有三种类型：陈述句、疑问句和特殊疑问句。
陈述句作为主语从句时，通常以that引导，例如：That he will come to the party is certain.疑问句作为主语从句时，通常以whether或what引导，例如：Whether he can come is still a question.特殊疑问句作为主语从句时，通常以who、what、which等引导，例如：Who will come is not clear.在理解了主语从句的基本概念和类型之后，我们还需要掌握如何正确使用主语从句。
使用主语从句时，需要注意以下几点：主语从句的引导词要使用正确；主语从句的时态要和主句保持一致；主语从句的语序要使用陈述句语序。
除了正确使用主语从句，我们还需要理解主语从句的省略情况。
在某些情况下，主语从句可以省略掉that，例如：It is certn (that) he will come.这种情况下，it是形式主语，真正的主语是that he will come。
高中英语主语从句是一个重要的语法知识点，需要我们熟练掌握并正确运用。
只有通过不断的练习和学习，我们才能在高考中取得优异的成绩。
（2）主语从句一般用什么引导词？引导词在从句中担任什么成分？（3）主语从句的时态有什么特殊之处？请举例说明。
（4）主语从句与宾语从句、表语从句有什么异同点？通过预习题，我们对主语从句有了初步的了解。
接下来，我们将深入学习主语从句的构成、用法以及与其他从句的区别。
九种英语主语从句
九种英语主语从句英语中，主语从句是一种非常常见的从句结构。
它可以用作句子的主语，起到引出或说明整个句子的作用。
以下是九种常见的英语主语从句的类型及示例：1. 名词从句（Noun Clauses）：名词从句作为主语，用于引出或说明某个事物或情况的真相、原因、目的等。
示例：- What he said is true.（他说的是对的。
）2. 代词从句（Pronoun Clauses）：代词从句用一个代词作为主语，描述或说明某人或某事。
示例：- It's important that we finish the project on time.（我们按时完成项目非常重要。
）- Whoever wants to join the club can sign up here.（想加入俱乐部的人可以在这里报名。
）3. 形容词从句（Adjective Clauses）：形容词从句用于修饰某个名词，作为主语起到描述或说明的作用。
示例：- What you just said is not relevant.（你刚才说的不相关。
）- Where he was born has always been a mystery.（他出生在哪里一直是个谜。
）4. 副词从句（Adverb Clauses）：副词从句用于描述或说明一个动作或状态的条件、原因、时间、地点等。
示例：- When he arrives, we can start the meeting.（他一到，我们就可以开始会议。
）- If you study hard, you will pass the exam.（如果你努力研究，你会通过考试。
）5. 不定式从句（Infinitive Clauses）：不定式从句用于说明一个动作的目的、结果等。
示例：- To win the game is our ultimate goal.（赢得比赛是我们的终极目标。
主语从句讲解
1)连接代词 what (whatever ),
who ( whoever) , which (whichever), whom, whose .
连接代词引导主语从句，在句中作主语，宾语，表语， 定语。
Which side will win is not clear. 定语 Who will write the poem has not been decided yet.主语 Whatever he did is right. 宾语 What the city will be still remains a mystery. 表语
It is certain that she will do well in her exam.
B. It + be + 名词词组 + that 从句 (an honour, a fact, a pity, etc）如：
It’s a pity that we can’t go.
C. It + be + 过去分词 + that 从句 (said, reported, thought, expected, decided, announced, etc。） 如：
The earth became so violent that it was not clear whether the shape would last or not.
It was not immediately obvious that water was to be fundamental to the development of life.
Why they suddenly disappeared still remains a mystery.
完整高中英语主语从句全面讲解
语法——Noun clauses as the subject主语从句如果一个句子在复合句中充当一个主语, 那么这个句子就是主语从句。
①That he finished writing the composition in such a short time surprised us all.②What we need are good doctors.③Whom we must study for is a question of great importance.1.主语从句的连接词1).连接词: that, whether①.That he will win is certain.②.Whether he'll join us in the discussion is of great importance.2).连接代词: who, what, which, whom , whose, whoever, whatever, whichever①.It is clear who is afraid of having a change in land ownership.②.What India needs is a law to make land ownership fairer.3).连接副词: when, where, why, how, how many, how much , how long, how soon, how often①When we'll start tomorrow will be told soon.②Where we can buy oxen is something we need to find out.③Why he came here is not known.④How we can protect the grain from damp needs to be discussed.【连接词】1. that——That t he earth moves around the sun is well known.2. whether——Whether he will come or not is not known yet.3. who ——Who will be sent there has not been decided.4. what——What you need is more practice.5. which——Which one is the best is not clear.6. when, where ——Where he has gone is a question.7. why, how——Why there is gravity is hard to understand.How he can earn a living in Britain remains a big problem.8. whoever、whatever、whichever可引导主语从句。
主语从句 讲解
主语从句主语从句：在复合句中作主语的句子。
主语从句的引导词主要有连词that, whether, if连接代词what, who, whom, whose，which, whatever, whoever, whichever等。
连接副词when，where，how, why1. that 引导的主语从句that 引导的主语从句一般位于句首，有时也用it作形式主语而把that从句后置。
that 在从句中不作任何成分，也没有实际意义，只起连接作用。
（从句位于句首时that不可省略，从句位于句末一般不能省略，在口语中偶尔可以省略）Eg: That he will come is certain.That China is a great socialist country is well known.It has been decided (that)they should start the project the next month.他们决定下个月开始这项工程2.whether/if 引导的主语从句whether/if 只起连接作用，有词义，是“是否”的意思。
whether 引导的主语从句可置于句首，这时不能用if 代替；if 引导的主语从句只能用it作形式主语，而把从句放在句末。
Eg: Whether he will be able to come is still a question.Whether the work can be completed on time is doubtful.=It is doubtful whether/if the work can be completed on time 这项工作能否按时完成还不确定。
3.连接代词和连接副词引导的主语从句连接代词和连接副词引导的主语从句要在句中作一定的成分（主语、宾语、表语、定语、状语、补语等），它们有一定的词义。
并且在任何情况下都不能省略。
史上最全的主语从句讲解及其练习
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 '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.例女口Whatever we do is to serve the people.注： whatever / whoever 的功用。
要注意和 whatever, whatever = anything that; whoever = anyone whowhoever引导的让步状语从句的区别。
女口： 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。
英语语法讲解之主语从句
英语主语从句主语从句：在复合句中充当主语成分的句子叫做主语从句。
常规主语从句，即句子在复合句中充当一个主语。
主语从句的时态：不受主句的时态影响和限制。
例如：That he finished writing the composition in such a short time surprised us all.What we need is time.It is certain that he will win the match.(1) 引导主语从句连词有that, whether, who, what, whatever 等(2) 连词位于句首不能省略(3) 主语从句大多数情况下视为第三人称单数主语从句引导词：1、由连词that 引导的主语从句。
例如：That you will win the medal seems unlikely.你想获得奖牌看起来是不可能的。
That you are so indifferent bothers me.你如此冷淡使我很烦恼。
That she survived the accident is a miracle.她在事故中幸免于难简直是奇迹。
2、用连接代词或连接副词if, whether 引导的主语从句。
例如：Which of them escaped from the prison is still a mystery. 他们哪一个是从监狱里逃跑的，仍然是个谜。
When they will come hasn’t been made pubic.他们什么时候来还不知道。
Whether she is coming or not doesn’t matter too much.她来不来都无关紧要。
3、用关系代词引导的主语从句。
例如：What you need is more practice.你所需要的是更多的训练。
What I want to know is this. 我想知道的就是这事。
主语从句超全讲解加练习
1〕从属连词：that，whether等.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.他肯定会赢。
Whether he’ll come here isn’t clear. 他是否会来这里还不清楚。
注意: 由that 引导的主语从句有时为了使句子结构平衡, 防止“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.2.That they should like each other is natural.这样就构成了下面一些常用句型:1) It is + n. +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 common knowledge that… …是常识______________(很遗憾)we lost the match._____________(这是事实)he cheated in the exam.2) It is + adj. +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________________(很可能)she will come back tomorrow.*_________________(很明显)this measure is effective.3) It +不及物动词+从句It happened that... 碰巧……It occurred to me that…我突然想起…_______________(刚好)I came into the office at that time.*____________________(我突然想起)I forget to sent the letter.4) It + be +过去分词+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..人们相信/认为……It is suggested that + (should〕do... 建议……__________________(据报道)20 people were killed in the accident.*_______________(建议)we should eat more vegetable and do more exercise.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。
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主语从句讲解（一）主语从句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。
定义:在复合句中充当主语的句子叫做主语从句.第一部分：常规主语从句，即句子在复合句中充当一个主语主语从句的时态：不受主句的时态影响和限制。
1.引导主语从句的关联词有三类：(1)从属连词that ，whether（1）That they were true sisters was clear from the facial resemblance between them.（2）Whether he’ll come here isn’t clear.(2)连接代词who, whom, whose, what, which, whoever, whatever, whichever，What she did is not yet known.How this happened is not clear to anyone.Whoever comes is welcome.（3）连接副词where，when, how, why2.主语从句是在复合句中充当主语的从句，其功同名词一样。
为了避免头重脚轻，常用it作形式主语, 而把真正主语放在句子末尾。
How the book will sell depends on its author.That he is the best student in the class is obvious.= It is obvious that he is the best student in the class.注意：主语从句不可位于句首的五种情况(1) if 引导的主语从句不可居于复合句句首。
(2) It is said , (reported) …结构中的主语从句不可提前。
例如：It is said that President Jingo will visit our school next week.(3) It happens…, It occurs… 结构中的主语从句不可提前。
例如：It occurred to him that he failed in the examination.(4) It doesn’t matter how/whether …结构中的主语从句不可提前。
例如：It doesn’t matter whether he is wrong or not.(5) 含主语从句的复合句是疑问句时，主语从句不可提前。
例如：Is it likely that it will rain in the evening?3主语从句用陈述语序。
关联词位于句首不能省略。
How he became a great scientist is known to us all.Who the watch belongs to is unknown.That he finished writing the composition in such a short time surprised us all.4 主语从句中注意的事项：1）. 在主语从句中，谓语动词一般用单数。
Whatever he says is of no importance.Whoever says this is wrong.但谓语动词用单数还是复数，不可一概而论，而要视句子的意义而定What I need is money.What I need are books.2）. what 与that 在引导主语从句时的区别what 引导主语从句时在从句中充当句子成分，如主语、宾语、表语，而that 则不然。
What you said yesterday is right.That she is still alive is a consolation.3）. 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，主语从句的连接词没有变化。
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。
1. It 作形式主语和it引导强调句的比较①主语从句常用it作形式主语，一般常用句型为：It is+{名词/形容词/过去分词}+主语从句例如：It is still a question whether she will come or not.It is strange that you should like him.It is still unknown which team will win the match.②而强调句则不同，它的结构是：It+be+被强调部分+that+从句强调主语：It is the times that produce their heroes.时势造英雄强调宾语：It is English that Prof.Lin teaches us.强调状语：It was in shanghai that I saw the film.判断是否是强调句有一个方法，就是将that以后的“句子的其余部分”拿出来单独看，看有没有缺成分，缺的是什么成分，再把谓语动词后面that前面的那部分，带到你认为缺成分的地方，如果放进去是一句完整的句子了，那就说明是强调句。
It is still a mystery what caused the accident.It is a mystery that his death remained.4）. whether与if. wwhether引导主语从句时, 常置于句首(此时whether不能用if代替), 也有后移的用法(此时whether可以用if代替)Whether they will come is not yet known.It is not yet known whether / if they will go there.whether和if的区别还有：1. 引导表语从句用whetherThe question is whether you should accept it.2. whether可以引导从句作介词的宾语I’m not interested in whether they’ll go or not.It depends on whether we have got enough money.3. whether可以直接跟动词不定式连用I didn’t know whether to laugh or to cry.She hasn’t decided whether to go or not.4. 用it 作形式主语的结构(1) It is ＋名词＋从句It is a fact that … 事实是…It is an honor that …非常荣幸It is common knowledge that …是常识(2) it is ＋形容词＋从句It is natural that… 很自然…It is strange that… 奇怪的是…(3) it ＋不及物动词＋从句It seems that… 似乎…It happened that… 碰巧…(4) it is＋过去分词＋从句It is reported that… 据报道…It has been proved that… 已证实…3. 主语从句不可位于句首的五种情况(1) if 引导的主语从句不可居于复合句句首。
(2) It is said , (reported) …结构中的主语从句不可提前。
例如：It is said that President Jingo will visit our school next week.(3) It happens…, It occurs… 结构中的主语从句不可提前。
例如：It occurred to him that he failed in the examination.(4) It doe sn’t matter how/whether …结构中的主语从句不可提前。
例如：It doesn’t matter whether he is wrong or not.(5) 含主语从句的复合句是疑问句时，主语从句不可提前。
例如：Is it likely that it will rain in the evening?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答案：高考题：CBBA 1~5 CBACD 6~10DDCAA 11~15 CBDAC 16~20 BDCAC。