(完整)高中英语主语从句全面讲解

1、 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。that he finished writing the composition in such a short time surprised us all.what we need are good doctors.whom we must study for is a question of great importance.1.主语从句的连接词1).连接词: that, whether.that he will win is certain.whether

2、hell join us in the discussion is of great importance.2).连接代词: who, what, which, whom , whose, whoever, whatever, whichever.it is clear who is afraid of having a change in land ownership.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

3、long, how soon, how oftenwhen well start tomorrow will be told soon.where we can buy oxen is something we need to find out.why he came here is not known.how we can protect the grain from damp needs to be discussed.【连接词】1. that that the earth moves around the sun is well known.2. whetherwhether he wi

4、ll come or not is not known yet.3. who who will be sent there has not been decided.4. whatwhat 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, howwhy there is gravity is hard to understand.how he can earn a living in britai

5、n remains a big problem.8. whoever、whatever、whichever 可引导主语从句。whoever comes will be welcome.whatever he did was right. whichever of you comes in will receive a prize.【小结】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, 但在连接代词 what 引导的主语从句后谓语动词的数要根据句意而定。it为了防止句子头重

6、脚轻，通常把形式主语 放在主语位置，真正主语后置。1. it is certain that he will win the match.2. it is true that he has made a very important discovery in chemistry.3. it is very likely that they will hold a meeting.4. it is strange that the man should have stuck to his silly ideas.5. it is a pity that we wont be able to go

7、 to the south to spend our summer vacation.6. it is still a mystery what caused the accident. 7. it is said that he has gone to shanghai.8. it seems that he has seen the film.【小结】1.以 that 引出的主语从句,常以形式主语 it 引导, 结构为：it is +形容词/名词/某些动词 ed + that 从句。2.在有些 that 从句中要用虚拟语气 (should +do/should +have done)。用

8、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 thatit is strange that很自然奇怪的是(3) it 不及物动词 从句it seems that似乎it happened that碰巧似乎it appears that据报道it has been proved thatit is said that已证实据说“it” 作形式主语代替主语从句的常见句型举例its +

9、adj. + that / wh- clausee.g. its clear / natural / certain that clauseits obvious that money doesnt grow on trees.e.g. its said / reported / known that clauseits believed that he will come next week.it s + n. + that / wh- clausee.g. its a shame / an honour / good news that clauseits still a question

10、 when well have our meeting.it + v. (n. / pron.) that /wh- clausee.g. it made us very happy that she was chosen.it appears that he forgot to sign the letter.whether 与 if 均为“是否”，但下列情况下只用 whether ：1. 引导主语从句并在句首 whether he will come is not clear.2. 引导表语从句 the question is whether hell come.3. whether 从句

11、作介词宾语 im not sure about whether well win.4. 引导让步状语从句时 whether you like it or not, youll have to do it.【注意事项】1. 主语从句位于句首时必须由连接词引导。 2. 主语从句后置时引导词 that 可省略。3. 主语从句位于句首时,不能用 if 引导。4. 主语从句后置时, 可以用 if 引导。练一练1. what makes this shop different is that it offers more personal services.2. these wild flowers ar

12、e so special i would dowhatever i can to save them.3. it is required in the regulations that you should not tell people the passport of your e-mail account.4. it is pretty well understood what controls the flow of carbon dioxide in and out of the atmosphere today.5. what made the school proud was th

13、at more than 90% of the students had been admitted to key universities.6. it now appears that they are in need of help.7. whoever knows the truth will tell you about it.8. it is good news that they will arrive in a few days.use the words below to fill in the blanks1. _ watch was lost is unknown.2. _

14、 you did is right.3. _ we will go for an outing tomorrow remains unknown.4. _ we need is time.5. _ will be our monitor hasnt been decided yet.whether what who whose whatever.whetherwhatwhateverwhosewho上面的空大家都填对了吗?上面每个句子都出现了的主语从句，大家能找到吗？1. whose watch was lost is unknown.2. whatever you did is right.

15、3. whether we will go for an outingtomorrow remains unknown.4. what we need is time.5. who will be our monitor hasnt beendecided yet.1. whose watch was lost is unknown.2. whatever you did is right.3. whether we will go for an outingtomorrow remains unknown.4. what we need is time.5. who will be our

16、monitor hasnt been decided yet.2. 在有些 that 从句中要用虚拟语气(should +do/should +have done)。他出生在何地还不知道。 2. 谁会赢得比赛还不知道。3. 谁来都欢迎。4. 那个人为什么被谋杀尚不知道。where he was born has not been found.why the person was murdered is still unknown.who will win the match is still unknown.whoever comes is welcome.5. what the teache

17、r said today was quite right.老师今天说的话是十分正确的。6. that they are badly in need of help is quite clear.他们急需帮助，这是十分明显的。7. whether they will sell the house is not yet decided.他们是否卖掉这所房子还没有决定。8. whatever was said here must be kept secret.这里说的话都应当保密。9. whoever makes mistakes must correct them.凡犯了错误的人都必须改正。10.

18、 it is a pity that she has made such a mistake.她犯了这样一个错误, 真是遗憾。11. it is believed that at least a score of buildings were damaged or destroyed.据信, 至少有二十座楼房遭到破坏或彻底毁掉。12. that they were true 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。13. whether hell come here isnt

19、 clear.他是否会来这里还不清楚。14. what she did is not yet known.她干了什么尚不清楚。15. 无论他说什么都不重要。whatever he says is of no importance16. 无论谁说这话都不对。whoever says that is wrong17. how this happened is not clear to anyone.这事怎样发生的，谁也不清楚。18. whoever comes is welcome.不论谁来都欢迎。19. 不管是谁犯了法，他都应该受到惩罚。whoever breaks the law should be punished。1. _