1、主语从句的定义与种类
主语从句在复合句中作主句的主语,引导主语从句的词有从属连词that, whether与连接代词who, what, which, whoever, whatever, whichever和连接副词when, where, why, how等. 比如:
That she was chosen made us very happy.
她当选了使大家非常高兴.
What caused the accident is a complete mystery.
是什么致使了这次事故还完全是一个谜.
Whether she will come or not is still a question.
她是不是来还是一个问题.
Which team will win the match is still unknown.
什么队会取得这场比赛还不了解.
Whoever comes to the party will receive a present.
参加聚会的每个人都将收到一份礼物.
When they will start has not been decided yet.
他们何时出发还没有决定.
注意:上述例句中的主语从句都是放在句首,但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. 比如:
It is a pity that she has made such a mistake.
她有如此一个错误,真是遗憾.
It depends on the climate whether they are going shopping today.
他们是不是今天去购物还要看天气状况.
如此就构成了下面一些常用句型:
1)It is + adj. / n. +从句
It is a pity/shame that...遗憾的是
It is possible that...非常可能
It is unlikely that...不可能
2)It +不及物动词+从句
It seems/appears that...好像
It happened that...碰巧
3)It + be +过去分词+从句
It is said that...据了解
It is known to all that...大家都知道
It is reported that...据报道
It is believed that...据信;大家相信
It is suggested that...有人建议
It must be pointed out that...需要指出
It has been proved that...已证明.比如:
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.
It is suggested that the meeting should be put off.有人建议会议延期召开.
It s reported that three people were killed in the accident and five were hurt badly.据报道,事故中三人丧生,五人重伤.
It is known to all that Taiwan is an inseparable part of China.大家都知道,台湾是中国不可分割的一部分.
[巩固训练]
1. Does _______ matter if he can t finish the job on time?
A. this B. that C. he D. it
2. It worried her a bit _______ her hair was turning grey.
A. which B. that C. if D. for
3. _______ is a fact that English is being accepted as an international language.
A. There B. This C. That D. It
2、学习主语从句需要注意的几个问题
1)引导词that与what
what既有引导主语从句有哪些用途,同时又在从句中作句子成分.这个时候what等于all that/everything that...,常译成所的;而that只起连接用途,本身无实质意义,在从句中也不担当任何句子成分.但that引导的主语从句放在句首时,不可以省略that.
比如:
What is done can t be undone.
已成定局,无可挽回.
What we can t get seems better than what we have.
大家得不到的东西好像比已得到的要好.
That we should work out a plan to deal with the present serious situation is important.
大家应该拟定一项计划来应对现在严峻的形势,这一点尤为重要.
That a new teacher will come to teach us geography is true.
一位新老师以后教大家地理,这是真的.
[巩固训练]
4. _______ what they told me really true?
A. Has B. Is C. Does D. Have
5. It matters little _______ a man dies, but _______ matters much is _______ he lives.
A. how; what; how B. how; it; how C. why; it; why D. that; what; that
6. _______ she couldn t understand was _______ fewer and fewer students showed interest in her lessons.
A. What; why B. That; what C. What; because D. Why; that
7. It is pretty well understood _______ controls the flow of carbon dioxide in and out the atmosphere today.
A. that B. when C. what D. how
8. _______ fashion differs from country to country may reflect the cultural differences from one aspect.
A. What B. That C. This D. Which
9. -What made her parents so angry?
- _______ she had failed in the examination.
A. As B. Because C. Since D. That
2)引导词if和whether
if和whether引导动词后的宾语从句时一般可通用,但介词后的宾语从句、主语从句、表语从句常由whether引导.
比如:
Whether she will go home or not is unknown.
她是不是回家还不能而知.
Whether we shall raise ducks or geese remains to be decided.
大家是养鸭还是养鹅仍没决定.
=It remains to be decided whether/if we shall raise ducks or geese.
[巩固训练]
10. _______ we ll go camping tomorrow depends on the weather.
A. If B. Whether C. That D. Where
3)其它引导词
连接代词who, which, whom, whose有各自的意义,起连接用途,并在从句中充当语、宾语、表语、定语等;连接副词when,where, why, how等有各自的意义,起连接用途,并在从句中充当状语.
[巩固训练]
11. -Do you remember _______ he came?
-Yes, I do. He came by car.
A. how B. when C. that D. if
12. It was a matter of _______ would take the position.
A. who B. whose C. whom D. whomever
13. -I drove to Zhuhai for the air show last week.
-Is that _______ you had a few days off?
A. why B. when C. what D. where
14. I read about it in some book or other, does it matter _______ it was?
A. where B. what C. how D. which
3、语气
在It is necessary / natural / important / strange...+ that-clause这种句型里,that所引导的主语从句中谓语动词用should +原形,表虚似语气.
比如:
It is necessary that the problem should be settled at once.
这个问题需要立刻解决.
It s strange that he should have gone away without telling us.
他居然没向大家说一声就走了,真是奇怪.
[巩固训练]
15. It is necessary that a college student _______ at least a foreign language.
A. masters B. should master C. mastered D. will master
4、以it作形式主语的主语从句与强调句型有什么区别
It be + adj./n. + that-clause与强调句型均有It be...that...之类的语言标志,但不一样的是:
①前者中的that从句是主语从句.若删掉其中的It be和that,则剩余部分不论结构还是语意都不可以成为一个句子;但若将后者中的It be和that去掉,则剩余部分的结构和语意仍能构成一个完整的句子.
②强调句型译为汉语时可加上正是或就是之类的字眼,而主语从句则不能.
请比较下面两个句子:
It is surprising that Mary should have won first place.
让人惊奇的是玛莉居然获得了1、.
It is Mary that has won first place.
正是玛莉得了1、.
第一句话中的It是形式主语,that引导的是主语从句.句中的It is和that没办法删除,一旦删除句子就不成立.
第二句是强调句型,其中的It is和that可以去掉,由于没It is和that句子仍然非常通顺.
Key: 1-5 DBDBA 6-10 ACBDB 11-15 AAADB
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