1、主语从句导入：观察并指出句子成分A tree has fallen across the road.You are a student.To find your way can be a problem.Smoking is bad for you.一 概念：主语：主语是指句子谈论的主题，说明的人或事物。也就是句中动作、行为、性质和状态的主体，一般位于句首主语从句：在句中充当主语的从句二基本结构关系词 简单句 谓语动词 宾语 同位语That he finished writing the composition in such a short time surprised us all.他在很
2、短的时间内写完作文让我们都很惊讶三 关系词(引导词)1 从属连词：that whetherthat 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 she left him cut him to the heart.That he will come is certain.注意：有时为了使句子结构平衡, 避免 “头重脚轻”, 常用 it 作形式主语, 而把从句放在后面。E.gThat she has made such a mistake is a pity.It is a pity that she has made such a mistake.
3、这样就构成了下面一些常用句型: 1) It is + adj. +从句 It is necessary that 有必要It is important that . 重要的是It is obvious that 很明显2) It +不及物动词+从句 It seems/appears that. 似乎 It happened that. 碰巧It occurred to me that 我突然想起3) 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
4、believed that. 据信;人们相信 It is suggested that. 有人建议 It must be pointed out that. 必须指出 It has been proved that. 已证明.4) It is + n. +从句 It is common knowledge that 是常识It is a surprise that . 令人惊奇的是It is a fact that 事实是由 whether 及其他连词引导的主语从句放在句首，句后都可。 Whether it will please them is hard to say.It is hard
5、to say whether it will please them.2. 连接代词：who whoever whom whose what whatever which whicheverWhat seems easy to some people seems difficult to others.Which side will win is not clear.注意：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 , that 则不充当任何成分无意义。 例如：What you said yesterday is right
6、.That she is still alive is a consolation3. 连接副词：when where how why 等Why he did it remains a mystery.When they will start is not known yet.How he became a great scientist is known to us all.Its certain.Well be late. Is he coming or not?We dont knowWhat does he want to tell us?We dont knowWhen will y
7、ou come back?It doesnt matter.四主语从句需注意的问题1 一个句子作主语时，主句的谓语动词应为单数。Eg Whether he will come depends on the weather.2 what 引导的句子作主语时，谓语动词的数由句子的内容决定（即由表语决定)。What I want is money. What we need are good booksWhat he said is reasonable. What we will do hasnt been decided.3 Where he was born and where he live
8、s now are not clear.Where and when he was born remains a secret.两个或两个以上的主从联合做主语，主句谓语动词应为复数。两个或两个以上的连词引导一个从句，主句谓语动词应为单数。4 Whether he will come isnt clear. (不能换成 if)It isnt clear whether /if he will come. (可以与 if 进行替换)（if 不能置于句首）5. It 作形式主语和 it 引导强调句的比较主语从句常用 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：
9、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.另外，还有一些比较多见的结构：It turned out that;It has been proved that;It happened/occurred that;It is well-known that等等而强调句则不同，它的结构是：It+be+被强调部分 +that+从句强调主语：It is the tim
10、es 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。6. 用于 It is important / natural / necessary / impossible that.
11、句型中, 主语从句应使用虚拟语气, 谓语动词用“should + 动词原形”的形式, should 有时有感情色彩。It be suggested/ advised/ ordered/requested that sb (should) do sth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)_ doesnt 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 be
12、ing discussed7(他为什么哭)_ is not clear.8It 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 obv
13、ious 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. Its probable that well 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 shocke
14、d me that Peter didnt tell anybody where he was.11. Who was responsible for the accident is not yet clear.12. Its a pity that you cant 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 t
15、hey 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 lo
16、oks like doesnt matter.23. How this happened is not clear to anyone.24. Whoever comes is welcome.25. Whether hell come here isnt clear.三用适当的引导词填空。1. It is likely _ he is the winner of this game. 很可能他是这场游戏的胜利者。2. _ she bought so many dictionaries is not clear.= It is not clear _ she bought so many di
17、ctionaries.不清楚她为什么买这么多字典。3. _ he was admitted into Beijing University made his teachers and parents happy. 他考上了北大，这让他的老师和父母很高兴。4. Its a pity_ you cant attend my birthday party.很可惜你不能参加我的生日聚会。5. _ we will build a new high school hasnt been decided. 我们是否要建新高中还没决定呢。6. _ breaks the law should be punishe
18、d.不管谁违法都应该受到惩罚。7. It is necessary _ the problem (should) be solved at once. 很有必要立刻解决这个问题。8. _ he was born is unknown. 他生于何时还不知道。9 It is possible _ he has stolen the car. 很可能他偷了小车。10. _ has broken the glass is unknown. 谁打破了玻璃现在还不知道。11. _ he wants is all here. 他所要的东西都在这里。12. _ he worked it out is stil
19、l a secret.他是如何把它做出来的还是一个秘密13. _ they makes in this factory are TV sets. 他们在工厂里所做的东西就是电视机。14. _ they would support us was a problem. 他们是否会支持我们还是一个问题。15. _ you want is yours. 你要哪个哪个就是你的。16. _ we need is money. 我们需要的是钱。17._ we arrive doesnt matter. 什么时候到没有关系。18. _ it was done was a mystery. 这是怎样做的是一个谜
20、。19 _ this happended is not clear to anyone. 这件事怎样发生的，谁也不清楚。20. _ I spend my summer is no business of yours. 我在哪里过暑假不关你的事。三选择题。 1. _ as much as one-fifth of all timber harvested is not used.A. The estimate B. The estimated C. They are estimated D. It is estimated that2. _ some mammals came to live i
21、n the sea is not known.A. Which B. Since C. Although D. How 3. _ we have achieved is attributed to the guidance of our parents.A. Whoever B. Whatever C. However D. That 4. _ wealthy does not necessarily mean that a man is greedy.A. For the reason that he is B. Just because he is C. The reason of bei
22、ng D. That he is 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. it6. _ 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 tha
23、t7. I am sure that _ she said is wrong.A. which B. all C. this D. what8. We lost our way in the forest, and _ made matters worse was that it was getting dark.A. that B. which C. it D. what9. _ or not is still uncertain.A. Hes coming B. If he is coming C. That coming D. Whether hes coming10. Its _ he
24、ll be able to come.A. doubt whether B. doubtful C. doubt it D. doubtful whether 11. _ he is at work in the heart of the big city or at home in the quiet suburb, Dicks life is tied to machines.A. Whether B. Till C. If D. Unless12. _ he saw both surprised and frightened him.A. That B. When C. What D.
25、Which13. _ is warm sunshine.A. What do we all need. B. What all we need C. What we need D. What we all need改错：1. Where shall we spend the holiday isnt decided.2. Your have made a mistake is a fact.3. That is certain that we can win.4. No matter who leaves the room last ought to turn off the lights.5
26、. It is important that a student learns a foreign language.答案：一、翻译1. Who will pick him up 2. Which class will win the football match3. Whether he can buy the plane ticket4.How we will go there5. What you told me just now6. When he will go abroad7. Why he cries8. that he is a beggar9. Who you will invite 10.Where we will hold the basketball match二、略三、1.that 2. Why ;why 3. That 4. that 5. Whether 6. Whoever 7. that 8. When 9. that 10. Who11. What 12. How 13. What 14. Whether 15. Whichever 16. What 17. When 18. How 19. How 20. Where 改错1 we shall2 that you have3 It is4 whoever 5 should learn
