练习（主语从句）
一、.关联词分类和基本句型：
(1)从属连词that。如：That they were indeed sisters was clear from the facial resemblance between them.
很明显，她们确是亲姐妹，她们的脸型很相似。
______ we need more equipment _____ quite obvious. 我们需要更多的设备，这是很明显的。
(2)从属连词whether。如：
Whether he’ll come here isn’t clear.他是否会来这里还不清楚。
______ he will join us won't _____ too much difference.他是否和我们一起干无所谓。
(3)连接代词who, whom, whose, what, which, whoever, whatever, whichever
连接副词where, when, how, why。如：
What you need is more practice. 你需要的是更多的练习。
Whoever wants it may have it. 谁要都可以给他。
_____she did ____ not yet known. 她干了什么尚不清楚。
_____ this happened is not _____ to anyone. 这事怎样发生的，谁也不清楚。
______ comes _____ welcome. 不论谁来都欢迎。
二、主语从句后置：
主语从句能用it作形式上的主语。常以it作形式主语的句型有：
A.It+be+形容词(obvious, true, natural, surprising, good, wonderful, funny, possible, likely, certain, probable, etc.)+that从句。如：
It is certain that she will do well in her exam. 毫无疑问她考试成绩会很好。
_____ _____ probable ______ he told her everything. 很可能他把一切都告诉她了。
B.It+be+名词词组(no wonder, an honour, a good thing, a pity, no surprise, etc.)+that从句。如：It’s _____ ______ that we can’t go.很遗憾我们不能去。
It’s ______ _______ that our team should have won the game. 我们没赢这场比赛真意外。
C.It+be+过去分词(said, reported, thought, expected, decided, announced, arranged, etc.)+that从句。如：
It is ______ ______Mr. Green has arrived in Beijing. 据说格林先生已经到了北京。
It is ______ _______ China has sent another man-made earth satellite into orbit.
据报道中国又成功地发射了一颗人造地球卫星。
D.It+seem, happen等不及物动词及短语+that从句。如：
It seems that Alice is not coming to the party at all. Alice似乎不来参加晚会。
_____ _______ ______ I was out that day. 碰巧我那天外出了。
E.It+doesn’t matter (makes no difference, etc.)+连接代词或连接副词引起的主语从句。如：
It doesn’t ______ _______ she will come or not. 她是否来这无关紧要。
It _____ _____ difference ______ we shall have the meeting. 我们在哪里开会毫无区别。
三、注意连接代词whoever, whatever, whichever等引导主语从句的含义：
_______ comes will be welcome. (whoever=the person who) 来的都是客。
_________ he did was right. (whatever=the thing that) 他所做的事情都是正确的。
________ _____ ______ comes in will receive a prize. (whichever=anyone of you who) 你们当
中不论哪个进来将会得到奖励。
四、主语从句与虚拟语气：
形容词为necessary, important, impossible, strange, natural, essential时，在“It + be + 形容词或过去分词+ 主语从句”中，主语从句要虚拟。
It is necessary that the problem ( ______ ) _____ ________ at once.
立刻讨论这个问题很有必要。
It is strange that he ( _____ ) have so many friends. 太奇怪了，他有那么多的朋友。
五、在高考题中考查的主语从句：（以下来自全国各地高考试卷）
1. It has been proved _________ eating vegetables in childhood helps to protect you against serious illnesses in later life.
A. if
B. because
C. when
D. that
2. ________ matters most in learning English is enough practice.
A. What
B. Why
C. Where
D. Which
3. ______ parents say and do has a life-long effect on their children.
A. That
B. Which
C. What
D. As
4. ________ puzzles the scientists how these creatures can survive in such severe conditions.
A. What
B. As
C. That
D. It
5. _____ leaves the room last ought to turn off the lights.
A. Anyone
B. Who
C. Whoever
D. The person
6. ______ you will be admitted to York University will be decided by the Admission Committee.
A. That
B. Whether
C. What
D. If
7．_______your father wants to know is________ getting on with your studies.
A. What; how are you
B. That；how you are
C. How；that you are
D. What；how you are
8.________he really means is ________he disagrees with us.
A. What …that
B. That …what
C. What …what
D. That …what
9.We sell handmade gifts. _____gift you order from us is unique for the special person!
A. Which
B. That
C. Whichever
D. What
主语从句、表语从句巩固训练题(附参考答案) 1. It has been proved _________ eating vegetables in childhood helps to protect you against serious illnesses in later life. A. if B. because C. when D. that 2. The last time we had great fun was ________ we were visiting the Water Park. A. where B. how C. when D. why 3. ________ matters most in learning English is enough practice. A. What B. Why C. Where D. Which 4. The traditional view is ______ we sleep because our brain is “programmed” to make use do so. A. when B. why C. whether D. that 5. ______ parents say and do has a life-long effect on their children. A. That B. Which C. What D. As 6.________ is our belief that improvements in health care will lead to a stronger, more prosperous economy. A. As B. That C. This D. It 7. ______ team wins on Saturday will go through to the national championships. A. No matter what B. No matter which C. Whatever D. Whichever 8. You are saying that everyone should be equal, and this is ______ I
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，whether 1）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”。 What we need is money. That he will come is certain. 2）whatever / whoever的用法（~ever=no matter ~---让步状语从句中） whatever / whoever可以引导主语从句,并在句中作主语、宾语、表语等,不含疑问意义。whatever相当于anything that; whoever 相当于anyone who。例如: Whoever(Anyone who) wants to enter into this school must take the exam. Whatever(Anything that) she did was right. 3. 连接副词when，where，how，why等。既有疑问含义,又起连接作用,同时在从句中充当各种成分。How this happened is not clear to anyone. When he will be back depends on the weather. When we’ll start tomorrow will be told soon. Where the test will be given is not yet decided. 4. 主语从句后置：为了避免主语冗长,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. 例: That we shall be late is certain. -- It’s certain that we shall be late. 1）用it 作形式主语的结构 A. It + be + 形容词+ that 从句 (obvious, true, surprising, good, wonderful, funny, possible, likely, certain, probable, etc.) 如：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 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 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：It is said that Mr. Green has arrived in Beijing. D. It + 不及物动词或短语+ that 从句( seem，happen, doesn’t matter ,turn out）。如： It happened that I was out that day. It doesn’t matter whether she will come or not. 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
1. _____ as much as one-fifth of all timber harvested is not used. A. The estimate B. The estimate C. They are estimated D. It is estimated that 2. _____ was once regarded as impossible has now become a reality. A. That B. Which C. Who D. What 3. _____ we have achieved is attributed to the guidance of our parents. A. Whoever B. Whatever C. However D. That 4. _____ you say now can’t make up for what you’ve done. A. No matter B. Whatever C. However D. That 5. Although _____ happened in this developed country sounds like science fiction, it could occur elsewhere in the world. A. which B. what C. how D. it 6. _____ she had forgotten to take her notebook. A. That occurred to her B. She occurred that C. To her that occurred D. It occurred to her that 7. I am sure that _____ she said is wrong. A. which B. all C. this D. what 8. We lost our way in the forest, and _____ made matters worse was that it was getting dark. A. that B. which C. it D. what 9. _____ occurred to him that he had forgotten to lock the door when he left home. A. This B. It C. That D. These 10. _____ or not is still uncertain. A. He’s coming B. If he is coming C. That coming D. Whether he’s coming 11. It’s _____ he’ll be able to come. A. doubt whether B. doubtful C. doubt it D. doubtful whether 12. It is _____ that the bridge has existed for more than three centuries . A. appeared B. risen C. said D. born 13. _____ he saw both surprised and frightened him. A. That B. When C. What D. Which 14. _____ is a spell of warm sunshine. A. What do we all need. B. What all we need C. What we need D. What we all need 15. _____ is a pity that he failed in the race. A. What B. That C. He D. It 16. _____ a spoonful of soil can tell us so much about the structure and early history of the moon. A. Remarkable B. Quite remarkably C. It is remarkable that D. It is remarkable 17. _____ you nominate will be elected. A. Who B. Which C. Whomever D. That’s 18. _____ book you borrow must be returned within a week.
主语从句练习题 一．翻译 1．(谁将去接他)_______________________________________________ is not decided. 2．(哪个班极会赢得这场足球赛)__________________________________ is not clear . 3．(他能否买到飞机票)______________________________________ doesn’t matter much. 4．(我们如何去那里)__________________________________________ is a question. 5．(你刚才告诉我的)_______________________________________ was really a surprise. 6．(他什么时候出国)_______________________________________ is being discussed 7．(他为什么哭)___________________________________________ is not clear. 8．It is clear______________________________________________(他是一个乞丐). 9．(你要请谁)______________________________________________ is not important. 10．(我们将在哪里举行篮球赛)____________________________________ is not clear. 二．找出下列句子中的主语从句及其引导词，并且指出引导词是否充当成分，充当什么成分。 1. That we shall be late is certain. 2. That the driver could not control his car was obvious. 3. It is certain that we shall be late. 4. It was obvious that the driver could not control his car. 5. Is it possible that they will come tomorrow？ 6. It is clear that he was telling the truth. 7. It’s probable that we’ll be a little late. 8. What caused the accident is a complete mystery. 9. It worried her a bit that her hair was turning grey. 10. It shocked me that Peter didn’t tell anybody where he was. 11. Who was responsible for the accident is not yet clear. 12. It’s a pity that you can’t go with us. 13. What he did is not yet known. 14. It is said that he has been there many times. 15. It is not yet clear who was responsible for the accident. 16. When they will have the sports meet is still a question. 17. It seems that he has lost something. 18. What he said at the meeting encouraged everyone. 19. What caused the accident was a broken bottle. 20. It remains a problem whether it is true. 21. Whoever breaks the law is sure to be punished. 22. What she looks like doesn’t matter.
语法要点剖析 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, why 1. 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： 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。 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。引导宾语从句的关联词与引导主语从句表语从句的关联词大致一样，在句中可以作谓语动词或介词及非谓语动词的宾语。 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。例如：He has told me that he will go to Shanghai tomorrow.他已经告诉我他明天要去 上海。 We must never think (that) we are good in everything while others are good in nothing. 我们决不能认为自己什么都好，别人什么都不好。
主语从句练习题 [即学即用] I. 用适当的词填空，使句子意思完整。 1. ______ he didn’t attend the meeting yesterday wasn’t quite clear. 2. The Foreign Minister said, “It is our hope ______ the two sides will work towards peace.” 3. ______ team will win the match is still unknown. 4. ______ comes to the party will receive a present. 5. ______ Mary has left is still a question. 6. It’s reported ______ three people were killed in the accident and five were hurt badly. 7. ______ he solved the problem successfully interested all of us. 8. We usually think ______ we can’t get seems better than what we have. 9. It is a fact ______ English is being accepted as an international language. 10. ______ is to be sent there to solve the problem hasn’t been decided. II. 下列各句中均有一处错误，请改正。 1. That the old man’s son wanted to know was where the gold had been hidden. 2. It is reported when China has successfully sent Shenzhou VI spaceship into space. 3. If he can finish his task on time is of great importance. 4. Whether the 2008 Olympic Games will be held in Beijing excited the whole nation. 5. After Yang Liwei succeeded in circling the earth, which our astronauts desire to do is walk in space. 6. Whatever leaves the room last ought to turn off the lights.
高中英语语法主语从句 第一节主语从句 1．考点解析。 1．主语从句一般分为三类：由what等代词引导的主语从句；由连词that 引导主语从句，多数情况下由it作形式主语，that从句放到句子后面去；由连接代词或连接副词（或whether）引导的主语从句。 What they are after is beauty. It is not your fault that we can’t arrive on time. When they will arrive has not been decided. 2. 由关系代词what引导的主语从句，也可由whatever（“所…的一切”）或 whoever（“一切…的人”）引导。 Whatever he wants is your support. Whoever comes will be welcome. 3. 大多数主语从句都可用it代替，作形式主语，把主语从句放在句尾。要注意it代替主语从句和it引导的强调句的区别。强调句的结构是it is/was….+that…，强调人是可把that 换做who，whom，whose。如强调的是状语时，也只能用that,而不能用when, where, how, why等。 It was in Paris that they fell in love with each other. It is the lady who was my English teacher. It was last semester that he won the first prize. 2. 试题详解。 1．______ he needs is more experience. A. Who B. That C. What D. How 2.It was because of the heavy snow ______ the train was late. A. why B. that C. so D. thus 3．It doesn’t matter ______ he likes or not. A. whether B. what C. when D. that 4______ he has won the Noble Prize has been proved to be true. A. What B. How C. It D. That 5．What he wants _______ to sleep more. A. are B. have been C. is D. were 6．______ we can begin this investigation is still a question. A. When B. Why C. What D. That 7．It is ______ that the highway will be open to traffic nest year. A. report B. reported C. reporting D. by report 8．______ fails to see this will make a big mistake. A. Whatever B. what C. wherever D. Whoever 9．It is a mystery _____ the prisoner escaped. A. why B. how C. what D. that 10．It was last summer _____ he graduated from the college. A. that B. when C. / D. where 3. 实战演练。 1. We didn’t know ______ she didn’t come. A. why B. that C. when D. it 2. It is still doubtful _______ she would play the part.
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.
主语从句 一、概念：在复合句中起主语作用得从句叫主语从句。 （一）连接词 从属连词：that、whether； 关系代词：who, what, which , whom, whose, whatever, whoever, whomever, whichever； 关系副词：when, where, how, why, however, whenever, wherever等； 例：What he said is true、 That you don’t like him is none of my business、 Whether the football game will be played depends on the weather、 主语从句得时态：不受主句得时态影响与限制。 （1）______ he finished writing the composition in such a short time ______(惊讶) us all、（2）______we 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 importance、 （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)主语从句得时态：不受主句得时态影响与限制。 （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引导得主语从句。 从属连词that，whether在主语从句中得作用只就是引导主语从句，在从句中不担任成分，不能省略。 例：__________ they will go is certain、 __________ she will come or not is still a question、 __________ she's coming or not doesn'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引导得主语从句可用it代替，that 不可省略。 用作it作形式主语得结构： （1）It is/was +形容词+that 从句 It’s natural that…很自然……It’s obvious that …显而易见…… It’s fortunate that …幸运得就是It’s (im)possible…（不）可能…… It’s unlikely that…不可能It’s strange that…奇怪得就是…… （2）It is/was +名词+that 从句 It’s a pity that…遗憾得就是……It’s a fact that …事实就是…… It’s good news that…就是好消息……It’s a wonder that…不足为奇…… It’s an honour that…非常荣幸……It’s a shame that…真就是可耻…… It’s common knowledge that …就是常识… （3）It +不及物动词+that 从句 It seems that…似乎……It happened that…碰巧…… It appears that…瞧来……It turns out that…结果…… （4）It is/was +过去分词+that 从句 It’s not known that………不得而知It’s said that…据说……
主语从句练习 练习1：划出下面句子的主语 A foreign language is a weapon in the struggle of life. Who is speaking, please? This is Jack speaking. Two will be enough. Smoking is very dangerous. To see is to believe. To do today's homework without the teacher's help is very difficult. “A” is an article. The teacher with two of his students is walking into the classroom. 练习2 what, whether, where, when， who, why, how or that. 1.(_____ is needed for success) is your hard work. 2.(______ they will arrive )has been told to the teacher. 3.(_____ we will go tomorrow )hasn’t been decided yet. 4.(____can join in the sport meet) is decided by the teacher 5.(________ it will rain or not) is not clear. 主语从句作主语时，谓语动词一般用单数形式。 练习3 Wh--ever 1. 你需要的是更多的经验。 ____________________ is more experience. 2. 谁最先到将得到奖品。 _________________________ will receive a prize. 3. 我所有的东西请随便使用。 ___________________ is at your service. 4. 不管他写什么都没关系。 _____________________ doesn’t matter. 5. 这里讨论任何事都应当保密。 ____________________________ must be kept secret. 练习4 Whether与if 1. ________we can solve this problem remains unknown. 2. ________this material can be used in our factory has not been decided yet. 3. ________people who choose red on the test are energetic or not has been
主语从句详解 一、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、主语从句主要有四类 （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. That you are so indifferent bothers me. That she survived the accident is a miracle. （2）用连词 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, 只能用whether. 例如：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. （3）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. What I want to know is this. Whatever we do is to serve the people. 注：whatever / whoever的功用
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, why 1. 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…
高中英语主语从句知识点整理 课 件www.5y https://www.doczj.com/doc/0f10138749.html, 1.定义：用作主语的从句叫做主语从句。 2.构成：关联词+简单句 3.引导主语从句的关联词有三类： 从属连词that。 例如：Thattheywereintruthsisterswasclearfromthefacialrese mblancebetweenthem.很明显，她们确是亲姐妹，她们的脸型很相似。 从属连词whether。 例如：whetherhe'llcomehereisn'tclear.他是否会来这里还不清楚。 连接代词： who whom whose what which whoever whatever
whichever 连接副词： where when how why 例如： whatshedidisnotyetknown.她干了什么尚不清楚。 Howthishappenedisnotcleartoanyone.这事怎样发生的，谁也不清楚。 whoevercomesiswelcome.不论谁来都欢迎。 whereveryouareismyhome----myonlyhome.你所在的任何地方就是我的家----我唯一的家。 注：主语从句能用it作形式上的主语。常以it作形式主语的句型有： A. It+be+形容词+that从句。 例如： Itiscertainthatshewilldowellinherexam.毫无疑问她考试成绩会很好。 Itisprobablethathetoldhereverything.很可能他把一切都告诉她了。
B. It+be+名词词组+that从句。 例如： It'sapitythatwecan'tgo.很遗憾我们不能去。 It'snosurprisethatourteamshouldhavewonthegame.我们没赢这场比赛真意外。 c.It+be+过去分词+that从句。 例如： Itissaidthatmr.GreenhasarrivedinBeijing.据说格林先生已经到了北京。 Itisreportedthatchinahassentanotherman-madeearthsat elliteintoorbit.据报道中国又成功地发射了一颗人造地球卫星。 D.It+seem,happen等不及物动词及短语+that从句。 例如： ItseemsthatAliceisnotcomingtothepartyatall.Alice似乎不来参加晚会。 IthappenedthatIwasoutthatday.碰巧我那天外出了。 E.It+doesn'tmatter+连接代词或连接副词引起的主语从句。