语法专题复习——名词性从句
语法复习学案：名词性从句
【语序问题】名词从句一定是“陈述句语序”（关联词+主语+谓语….）I don’t know when he came back.（一）名词性从句的种类1、主语从句: 名词性从句作主语常用先行词it做形式主语，而将从句置于句末。
That you missed the concert is a pity.→________________________________________________. a. It + be +形容词+ that-从句It is necessary that…It is important that…It is obvious/clear that…b. It + be + -ed 分词+ that-从句It is believed that…It is known to all that…It has bee n decided that…c. It + be +名词+ that-从句It is common knowledge(常识) that…It is a surprise that…It is a fact that…d. It +不及物动词+ that-从句It appears/seems (to sb)that…似乎/好像It happens that…碰巧It occur red to me that…某人突然想到2、宾语从句：在复合句中作宾语的名词性从句(及物动词，介词和形容词后)（1）介词后的宾语从句不能用that引导（特殊介词except/but“除外”除外）（2）“形容词宾语”主要是be +adj +介词+sth/what从句; be + adj + that从句We hope (that) you will enjoy your stay here. Tell me why you don’t like school.Don’t ask about what the meeting is for. We are certain that this is true.（3）动词+ it +从句（it为形式宾语，无含义）hate, love, like, take , owe, have, see to不能直接加宾语从句。
高三英语语法复习之名词性从句
1.)由连接词that引导的宾语从句
由连接词that引导宾语从句时， that在句中不担任任何成分，在 口语或非正式的文体中常被省 去，但如从句是并列句时,第二 个分句前的that不可省。
He has told me that he will go to Shanghai tomorrow.
注意:在demand, order, suggest, advise, decide, insist, desire, request, command等表示要求、 命令、建议、决定等意义的动 词后，宾语从句常用 “should+ 动词原形”。
I know that he studies English every day.
I know that he studied English last term.
I know (that) he will study English next year.
We all know that he has studied English since 1998.
I insist that she (should) do her work alone.
The commander ordered that troops (should) set off at once.
但是, 如果suggest作“表明、暗 示”讲, insist作“坚持说、坚持 认为”讲，则其后的宾语从句中 应该用陈述语气。
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
高考英语语法之名词性从句
1.名词：表示人或事物的名称的词叫名词。 2.名词的句法作用：名词在句中主要作主语、宾 语、表语和同位语。另外还可以作定语、状语。 3.名词性从句： 在英语的句子结构中，本来该由名词充当的主 语、宾语、表语和同位语，由一个句子来充当， 这个句子就叫名词性从句。 4.名词性从句的种类： 根据名词性从句在句子中所充当的不同成分， 名词性从句可以分为主语从句、宾语从句、表 语从句和同位语从句。
2.When he will go to America is not yet fixed.
(It is not yet fixed when he will go to America.)
宾语从句
在复合句中作主句的宾语.引导 词有连词that (that 常可省 略),whether,if; 代词有who, whose,what ,which
表语从句
在复合句中作主句的表语. 引导词有连词that (that 不可 省),whether; 代词有who, what ,which;
副词 when ,where, how, why
等.
The problem is that we didn’t get in touch with him.
This is how Henry solved the problem. His suggestion is that we (should) finish the work at once.
(4).It is not yet decided which cash crop will be produced next year. (5).Whatever he said was right.
(6).Whoever goes there must get ready by 6 o’clock.
7.语法专攻——名词性从句
主语从句
做主语用的名词性从句，因其在复合句中做主语， 又称主语从句，引导主语从句的有连词that ， whether， 连接代词who ，what ，which， 连接 副词when，where， how， why等。 That she left him cut him to the heart. Whether it will please them is not easy to say. What seems easy to some people seems difficult to others. Why he did it remains a mystery.
表语从句
在从句中作表语的从句称作表语从句。 （1）that 引导的表语从句 that 仅起连接作用，无意义，在句中不作任何成 分，通常不可省略。这种从句往往是对主句主语 的内 容起进一步解释的作用。 The chance is that one smoker in four will die from smoking.
2. whether 引导的表语从句 连接词whether起连接作用， 意为“是否、究竟、到 底”（注意：if不能引导表语从句) 在句中也不作任何 成分。 The question is whether what man will turn up in time. 3. what, which, who, whom, whose引导的表语从句 连接代词what, which, who, whom, whose除在句子 中起连接作用外，还可在从句中从当主语、表语、定 语，且各有各的词义。
书面表达中的名词从句应用
同位语从句
连接词 ： （1）从属连词：that, whether等。 He told me the news that he would come home from aboard soon. 他告诉我一个消息,他马上要从国外回国。 （2）连接代词：what, who, which等。 I have no idea which one I should choose. 我不知道该选哪个。（定语）
高考语法专题复习-名词性从句_(郑州四中名师特供)
高考语法专题复习-名词性从句（郑州四中名师特供）概念名词性从句，就是句法功能与名词相同的从句，也就是在整个句子中可以作主语、宾语、表语和同位语的从句。
一、<核心考点>问题一：名词性从句分为哪几种？问题二：判断下列属于哪类名词性从句。
1.She said (that) the book was based on a true story. （）2.That he won first prize delighted me.（）3.The advantage is that we know more about medicine today.（）4.He told me the news that our team had won the game. （）5.I asked her whether/if she agreed. （）6.Tom is no longer what he used to be.（）7.I worry about whether I hurt her feelings.（）8.The question is whether they will support me. （）9.He must answer the question whether he agrees with it or not.（）10.That was where we camped last time. ( )11.Tell me whether or not you’re interested in English. （）12.The question is which he will choose. （）13.What we need is more time. （）问题三：名词性从句三个要素？1.语序：跟陈述句语序相同，主语在前，谓语动词在后。
如：Why he did it remains a puzzle.2.时态一致：当主句谓语是现在式时，从句谓语可根据情况用不同时态，若主句谓语为过去式时，从句谓语通常也用过去式。
高考英语语法总复习名词性从句
• 一、名词性从句的种类
• 名词性从句是起名词作用的从句，包括主语从句、宾语从 句、表语从句、同位语从句。
请思考：
1、English is very useful for us . 2、We need to master English well. 3、The subject I am interested in is English. 4、He want to learn the language , English .
• that引导主语从句时，常用it作形式主语，常 见句型有： • ①it＋be＋形容词(如： obvious，true，natural， surprising，good，wonderful，funny，possible， likely，certain，probable，evident，clear， apparent等)＋that从句。 • It is evident that lung cancer is closely related to smoking.
注意：
1. 在口语或非正式问题中，引导宾语从句的that常省略，但 在下面情况下，that 一般不省略 （1） 当一个句子有两个或多个并列的宾语从句时，除第一 个从句的that外，都不可省略。 He told me (that) the power would be cut off and that I should get out. （2）形式宾语it后的that及介词后面的that不能省略。 2. 如果主句主语是第一人称，谓语动词是think ,consider, believe, suppose, expect, fancy, guess, imagine等，后面的宾语 从句含有否定意义，否定转移。 I don't think this dress fits you well. 我认为这件衣服不适合你。
初中英语语法——名词性从句讲解及练习
初中英语语法——名词性从句讲解及练习什么是名词性从句名词性从句是指在句子中充当名词的从句。
它可以充当主语、宾语、表语和宾语补足语等。
名词从句的引导词有：that, if, whether, who, whom, whose, which, what, when, where, why, how等。
名词性从句的功能及结构主语从句主语从句在句子中作主语，通常使用that引导。
例如：宾语从句宾语从句在句子中作宾语，通常使用that, if, whether, what, when, where, why等引导。
例如：- She asked me what I wanted for dinner.（她问我晚饭想吃什么。
）what I wanted for dinner.（她问我晚饭想吃什么。
）表语从句表语从句在句子中作表语，通常使用that, if, whether等引导。
例如：- My only hope is that the weather will be good tomorrow.（我唯一的希望是明天天气好。
）that the weather will be good tomorrow.（我唯一的希望是明天天气好。
）- The problem is whether he can solve it.（问题在于他能否解决。
）whether he can solve it.（问题在于他能否解决。
）宾补从句宾补从句在句子中作宾补，通常使用that, if, whether等引导。
例如：- They made me believe that anything is possible.（他们让我相信一切皆有可能。
）that anything is possible.（他们让我相信一切皆有可能。
）- I find it amazing that she can speak five languages.（我发现她能说五种语言真是令人惊奇。
高中语法专项复习 名词性从句
语法专项复习：名词性从句一、名词性从句的类型：1.主语从句(Subject Clause)：充当句子的主语；置于句首或句末(常用“it”作形式主语)例句：Whether Native Americans arrived in California 15,000 years ago or 14,000 years ago is not important.*从句作主语时，谓语动词一般用单数。
但是what和who引导主语从句时，有时主句的谓语动词的数应与主句中表语的名词保持一致。
例句：1. What they bought was water.2. What they bought were books.“It”作形式主语的句型：1) It is/was +名词( no wonder, an honor, a good thing, a pity, no surprise…)＋主从例句：It is a pity that we can’t go.2) It is/was ＋形容词(obvious, natural, surprising, wonderful, possible, likely,certain…)＋主语从句例句：It is clear that Tom has returned.3) It is/was＋过去分词(said / reported / believed / known / thought / expected /decided / announced / arranged…)＋主语从句例句：It is said that President Jiang will visit our school next week.4) It＋动词(happens /occurs / seems…) ＋主语从句例句：It occurred to him that he failed in the examination.5) It doesn’t matter how/whether…例句：It doesn’t matter whether he is wrong or not.2.宾语从句(Object Clause)：作句子的宾语；位于动词或介词之后。
高中英语语法复习--名词性从句
2. that在宾语从句中 在宾语从句中
形式宾语) 宾补+that从 在主+谓+it (形式宾语 +宾补 谓 形式宾语 宾补 从 真正宾语)的句型中 句(真正宾语 的句型中不省略 真正宾语 的句型中不省略 We must make it clear that we mean what we say. 由连词and连接的两个由 连接的两个由that引导的 由连词 连接的两个由 引导的 宾语从句中,第二个 第二个that不省略。 不省略。 宾语从句中 第二个 不省略 He told me (that) he would come and that he would come on time.
形式主语it 形式主语
为避免主语冗长,句子头重脚轻,经常用 作 为避免主语冗长,句子头重脚轻,经常用it作 形式主语,主语从句放在后面作真正的主语。 形式主语,主语从句放在后面作真正的主语。 1. It is certain that he will succeed. 2. It is not known whether he will go there. 3. It has not been decided yet when they’ll start the project.
1. 他发现很难使别人理解他 他发现很难使别人理解他.
He found it difficult to make himself understood.
2. 我认为我们保持冷静很重要 我认为我们保持冷静很重要.
I think it important that we should keep calm .
1. It’s likely / possible / important / necessary / 很可能/重要的是……/必要的 clear that… 很可能/重要的是 / 是……/很清楚 /很清楚…… 2. It’s said / reported that… 据说/据报道 据说/据报道…… 3. It seems / appears / happens that… 似乎/好 似乎/ 碰巧...... 像/碰巧...... 4. It’s been announced / declared that…已经 已经 通知/宣布…… 通知/宣布 5. It’s no wonder that… 并不奇怪/无疑 并不奇怪/无疑…… 6. It’s a pity / a fact / common knowledge (众 众 所周知) 俗话说) 所周知)/ a common saying (俗话说 that… 俗话说
高考英语语法复习之名词性从句
3 . 宾语从句 I hope (that) everything is all right.
that 引导的宾语从句之注意：
(1)that在引导宾语从句时，常可省略，但如果有两 个以上的宾语从句时，最后一个从句的that不能 省略。如： I know (that) he has just graduated from college and that he is looking for a job.
状语
①When he will go is unknown. ②I wonder why he tried to avoid me. ③This room is where I was born. ④This is how we work.
①Pay attention to what the teacher said. ②Who kept the door open all night was unknown.
whomeve 主语、宾语 r 无论谁/ 无论哪个( 、表语、定 / which 些)/无论什么 语 ever/ whatever
整“呼应”。如：
She remembered that she had left her wallet at
the school gate.
Our teacher said that light travels faster than
sound.
4．
同位语从句
同位语从句在句中作某一名词的同位语，一般位
于该名词(如：news, fact, idea, suggestion,
promise等)之后，说明该名词的具体内容。如：
I have no idea when he will be back.
高三语法复习 名词性从句
what (什么) / which ( 表选择, 哪一 个、哪一些)
1. ---Do you know ________ what Mr Black’s address is ?
---He may live at No. 18 or No. 19 of Bridge which Street. I’m not sure of _________. 2. I read about it in some book or other. Does it matter _______ which it was?
小结:it 作 形式主语的四个主要句型
1.it +be+形(possible/certain/surprising_) +that从句 2.it+be+名(no surprise/no wonder/a pity_) +that 从句 3.it+be+过去分词(said/reported/thought/ believed/decided_)+ that从句 4.it+不及物动词（happen_）+that 从句
1： That What
二、宾语从句典型错误
1.Idon’t believe that the teacher will not believe not consider our suggestions. 2. She was praised for what she had had she done. if / whether 3. He wants to know I still study English. 4. I am interested in if he can do whether it in such a short time. 5.It is generally considered unwise to give a child nowhatever matter what he or she wants.
高考英语语法专题汇总(三)：名词性从句(附例题及电子版)
2020高考英语语法专题汇总（三）：名词性从句(附例题及电子版)在复合句中起名词作用的从句叫作名词性从句。
包括主语从句、宾语从句、表语从句和同位语从句。
注：由于名词性从句在句中不同的句法功能（即名词性从句在复合句中，能充当主语、宾语、表语、同位语等。
）相应地，名词性从句可以分为主语从句、宾语从句、表语从句和同位语从句。
2主语从句主语从句可直接放在句首，也可用形式主语it代替，而将主语从句后置。
•that引导的主语从句1)that引导的主语从句置于句首（that此时在从句中不充当任何成分，无含义，只起连接作用，不能省略）That the earth moves around the sun is known to all.注：从句作主语，谓语动词用单数形式。
2)在that引导的主语从句中，常用it作形式主语，that引导的真正的主语从句后置，常见的此类句型有：①It+系动词+形容词+that从句。
常用于这种结构的形容词有：It is likely that he can’t come to the meeting.It is obvious that you have made a big mistake.注：It isnecessary/important/surprising/strange/unthin kable/unbelievable/incredible that+主语(should)+动词原形+其它。
例：It is necessary that a college student (should) master one or two foreign languages.It is strange that you (should) trust Jane.②It+系动词+名词+that从句。
常用于这种结构的名词有：It is a pity that you didn’t attend the lecture yesterday.It is no wonder that you’ve achieved so much success.③It+ be+过去分词+that从句。
高三语法复习专题八 名词性从句
名词性从句考点精析在句子中起名词作用的从句叫名词性从句(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，名词性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。
(一)引导名词性从句的连接词1．引导名词性从句的引导词可分为三类连接词：(不充当从句的任何成分)that, whether, if连接代词：what, whatever, who, whoever, whom, whose, which连接副词：when, where, how, why2．不可省略的引导词(1)介词后的引导词不可省略。
(2)引导主语从句和同位语从句的引导词不可省略。
如：That he was chosen president made us very happy.We heard the news that our team had won first prize.3．whether与if均为“是否”的意思。
但在下列情况下，whether不能被if所取代(1)引导主语从句(包括从句在句首的位置)应当用whether，不用if，如：Whether our team will win remains a problem.Whether he will come, I am not sure.(2)引导表语从句用whether，不用if，如：The question is whether you have enough money now.(3)whether可以引导从句作介词的宾语，而if则不能，如：I’m not interested in whether they’ll come or n ot.It depends on whether we have got enough time.(4)whether可以直接和动词不定式连用，而if则不能，如：I didn’t know whether to wait or to leave.Mike hasn’t decided whether to make a telephone call or not.(5)引导同位语从句用whether，不用if，如：The news whether they will attend the party is not known yet.大部分引导词引导的主语从句都可置于句末，前面用it充当形式主语。
语法专项·精讲—名词性从句
︱高中总复习︱一轮·英语
考点三 what,wh-ever引导的名词性从句 1.what引导名词性从句时,what在从句中作主语、宾语、表语、定语。
“Every time you eat a sweet, drink green tea.” This is what my mother used to tell me.
︱高中总复习︱一轮·英语
名词性从句
语法专项·精讲 跟踪训练·运用
︱高中总复习︱一轮·英语
语法专项·精讲
细筛选·巧拓展
考点一 名词性从句的种类
1.主语从句
it作形式主语,常见的句型有:
(1)It+be+形容词(obvious,true, natural, surprising, important, good,
︱高中总复习︱一轮·英语
8.Your support is important to our work.You can do 9.The most pleasant thing of the rainy season is
entirely free from dust.
helps. one can be
2.表语从句 (1)because引导的表语从句强调原因,而why引导的表语从句强调结果。 If I’m a bit sleepy,it’s because I was up all night. 如果我有点困,是因为一夜没睡。 That’s why I object to the plan. 这就是我反对这个计划的原因。
︱高中总复习︱一轮·英语
4.However, there are a number of other reasons that might explain
高中英语复习语法专练--名词性从句
高中英语复习语法专练--名词性从句高中英语复习语法专练--名词性从句第十二章名词性从句17. 名词性从句在句子中起名词作用的句子叫名词从句 (Noun Clauses）。
名词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。
17.1 引导名词性从句的连接词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, why不可省略的连词：1. 介词后的连词2. 引导主语从句和同位语从句的连词不可省略。
That she was chosen made us very happy.We heard the news that our team had won.比较：whether与if 均为"是否"的意思。
但在下列情况下，whether 不能被if 取代：1. whether引导主语从句并在句首2. 引导表语从句3. whether从句作介词宾语4. 从句后有"or not"Whether he will come is not clear.大部分连接词引导的主语从句都可以置于句末，用 it充当形式主语。
It is not important who will go.It is still unknown which team will win the match.17.2 名词性that-从句1）由从属连词that引导的从句叫做名词性that-从句。
That只起连接主句和从句的作用，在从句中不担任任何成分，本身也没有词义。
名词性that-从句在句中能充当主语、宾语、表语、同位语和形容词宾语，例如：主语：That he is still alive is sheer luck. 他还活着全靠运气。
【英语】名词性从句专题复习经典
【英语】名词性从句专题复习经典一、名词性从句1．________ is the centre of our planetary system was a difficult concept to grasp in the Middle Ages.A. It's the sun and not the earthB. The sun and not the earthC. Being the sun and not the earthD. That the sun and not the earth【答案】 D【解析】【分析】句意：太阳而不是地球是我们行星系统的中心，这在中世纪是一个很难理解的概念。
分析句子可知，整个句子为主系表结构，was为系动词，它之前的都为主语，且主语由句子来充当，句子结构以及句意完整，所以连词代词为that。
故选D。
【点评】考查名词性从句，本题涉及that引导的主语从句。
2．Some people believe _______ has happened before or is happening now will repeat itself in the future.A. whateverB. wheneverC. whereverD. no matter what【答案】 A【解析】【分析】句意：一些人认为之前发生的或现在正在发生的任何事情在将来都会重复发生。
Whatever has happened before or is happening now是一个主语从句，whatever既引导起这个主语从句，也在句中做主语。
BC项都属于副词的性质，都不能做主语，通常只能做状语；no matter what只能用来引导状语从句，故选A。
【点评】考查名词性从句，本题涉及"特殊疑问词+ever"引导的主语从句。
3． is even more important is the earth cooled down, water began to appear on its surface.A. When; that; whenB. What; whether; asC. What; that; asD. lt; whether; as 【答案】 C【解析】【分析】这题考查从句的用法，第一空填what引导主语从句，在主语从句中what做主语，第二空填that引导表语从句，在表语从句中，as是引导时间状语从句，句意是：甚至更重要的是：随着地球的冷却，水开始出现在表面。
语法复习10：名词性从句
语法复习10：名词性从句在句子中起名词作用的从句叫名词性从句(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、同位语等，因此根据它在句中不同的语法功能，名词性从句可分为主语从句、宾语从句、表语从句和同位语从句。
其关联词有连接词that，if，whether；连接代词who，whom，whose，what，which，whoever，whomever，whatever，whichever；连接副词when，where，why，how等。
一．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。
【完成例句】根据句意选词填空(that, if, whether, why, when, what)(1) That he will succeed is certain.(2) Whether he will go there is not known.(3) What he said is not true.(4) When the meeting will be held has not been decided yet.【结论】①that－从句，从句为一个句意完整的陈述句，没有具体意义，不充当句子成分，只起标志性作用，但that 不能省略。
②whether －从句，从句来源于一般疑问句，whether不能省略，意为“是否”，不能用if替换。
③特殊疑问词－从句，从句来源于特殊疑问句，特殊疑问词不能省略，意思为特殊疑问词本来的意思，在从句中充当句子成分。
What he wants to tell us is not clear. 他要跟我们说什么，还不清楚。
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名词性从句【知识要点】一、在句中起名词作用的从句叫名词性从句，它包括主语从句、宾语从句、表语从句和同位语从句。
如：Whether he will come here or not is unimportant to me.（主语从句）I don’t know what he means.（宾语从句）I’m glad that you are here.（宾语从句用在形容词之后）The teacher is satisfied with what you have done.（介词宾语从句）That was because he was ill.（表语从句）The news that he got killed in the race surprised us all.（同位语从句）二、引导名词性从句的连接词1.that引导的从句如果作介词宾语只可用在except，in，but，besides等少数介词后。
如：I could say nothing but that I’m sorry.that引导的从句可作it的同位语从句。
如：You may depend upon it that all the goods will be delivered in time.2.that引导宾语从句时可省略；引导其他名词性从句时，一般不省略，特别是引导主语从句且位于句首时。
如：That the earth is round is true.The fact that he is a thief got around.注意：下面一句中，第一个that可省略，第二个that不可省略：He said（that）he had been working here for ten years and that he wanted to go home.3.whether与if引导名词性从句时的区别。
（1）在引导宾语从句时whether与if可互换，但如果和or not连用则只用whether。
如：I don’t know whether or not he can stay here longer.（2）如果宾语从句是否定结构，则用if而不用whether引导。
如：He asked me if I wasn’t going there.（3）介词宾语从句只能用whether引导。
如：I’m not interested in whether he is rich.（4）引导主语从句、表语从句或同位语从句一般多用whether。
如：The question is whether you can do it yourself.The question whether he will come here himself isn’t decided yet.Whether it will do us harm or good remains to be seen.（5）用it作形式主语时，whether或if都可以引导主语从句。
如：It is not clear to me whether/if he likes the present.4.注意what/whatever；who/whoever；which/whichever的区别。
试比较下列句子： Whoever will go to the concert please signs your name here.=Anyone who will go to theconcert please signs your name here.Who will go to the concert isn’t known.=It’s unknown who will go to the concert.He won’t believe whatever she says.=No matter what she says，he won’t believe her. Whichever toy you want is yours.=No matter which toy you want，it is yours.5.注意how long/how soon/how often/how much的区别。
How long will he stay here?他将在这里待多久？How soon can you be ready?你多久能准备好？How often do you visit her?你多长时间去探望她一次？How much is that dress?那件衣服多少钱？6.当主句谓语动词表示不肯定或怀疑时，宾语从句用whether/if引导；表示有把握时用that 引导。
如：I doubt whether/if he can win the match.I don’t doubt th at he can win the match.7.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。
如：What you said yesterday is right.That she is still alive is a fact.8.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。
如：It is said that President Jiang will visit our school next week.（right）That President Jiang will visit our school next week is said.（wrong）（3）It happens...，It occurs...结构中的主语从句不可提前。
如：It occurred to him that he failed in the examination.（right）That he failed in the examination occurred to him.（wrong）（4）It doesn’t matter how/whether....结构中的主语从句不可提前。
如：It doesn’t matter whether he is wrong or not.（right）Whether he is wrong or not doesn’t matter.（wrong）（5）含主语从句的复合句是疑问句时，主语从句不可提前。
如：Is it likely that it will rain in the evening?（right）Is that will rain in the evening likely?（wrong）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。
1.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。
被强调部分指人时也可用who/whom。
如：It is a pity that you didn’t go to see the film.你没去看那场电影真是遗憾。
It doesn’t interest me whether you succeed or not.你成功与否对我没有什么吸引力。
2.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 knowle dge 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 is ＋不及物动词＋从句It seems that...似乎……It happened that...碰巧……4)it ＋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。
如：据说江主席下周要来我校视察。
It is said that President Jiang will visit our school next week.(right)That President Jiang will visit our school next week is said.(wrong)3)It happens...，It occurs... 结构中的主语从句不可提前。
如：他考试没及格。
It occurred to him that he failed in the examination.(right)That he failed in the examination occurred to him.(wrong)4)It doesn’t matter how/whether ...结构中的主语从句不可提前。
如：他是不是错了，这一点不重要。
It doesn’t matter whether he is wrong or not.(right)Whether he is wrong or not doesn’t matter.(wrong)5)含主语从句的复合句是疑问句时，主语从句不可提前。
如：傍晚有可能下雨吗？Is it likely that it will rain in the evening? (right)Is that will rain in the evening likely? (wrong)4.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。
如：What you said yesterday is right. 你昨天说的是对的。
二、宾语从句宾语从句就是在复合句中作宾语的名词性从句，通常放在主句谓语动词（及物动词）或介词之后。
1.作动词的宾语1)由that引导的宾语从句（that 通常可以省略）,如：I heard that he joined the army. 我听说他参军了。