1、GRAMMAR主语从句 在复合句中充当句子主语的从句叫主语从句。【要点精讲】一、whether, who, what, which, when, where, how, why等都可引导主语从句。如：Whether we will go for an outing tomorrow remains unknown.What I need most now is more time.二、that引导主语从句时，that在句中不作句子成分，且无实际意义。当that引导的主语从句置于句首时，that不能省略；如果用it作形式主语，而把主语从句放在句末时，that可以省略。如：That I will
2、take an English test next week is certain.It is a pity (that) you made such a careless mistake.三、it作形式主语的几种常见句型It + be + n. +主语从句。常用于此句型中的名词有fact, rule, pleasure, truth, pity等。如：It is a fact that English is being accepted as an international language.It + be + adj. +主语从句。常用于此句型中的形容词有true, important,
3、 necessary, clear, certain等。如：Its true that the earth is round.It + v. +主语从句。常用于此句型中的动词有seem, appear, happen, follow等。如：It appeared that she was older than she really was.It + be +动词-ed形式+主语从句。常用于此句型中的动词-ed形式有known, said, proved, asked, suggested等。如：Its well known that Thomas Edison invented the ele
4、ctric lamp.注意：if和whether都可引导主语从句，但if不能引导位于句首的主语从句。但如果用it作形式主语，而把主语从句放在句末时，也可以用if引导。如：Whether Tom really saw Sharon was doubtful.It was doubtful if / whether Tom really saw Sharon.表语从句放在be, seem, appear等连系动词之后充当表语的句子叫表语从句。【要点精讲】一、由that, whether, as if / though引导的表语从句 The trouble is that I have lost h
5、is address. The question is whether they will go by plane or by train. It sounds as if / though someone is knocking at the door.二、由because和why引导的表语从句 This is because the weather here is cold and wet.（强调原因） Thats why Tony got angry with me. （强调结果）三、由连接代词和连接副词引导的表语从句引导表语从句的连接代词who, whom, whose, what,
6、which, whoever, whatever, whichever在从句中充当主语、宾语、定语或表语；连接副词when, where, why, how在从句中充当状语。如： He has become what he wanted to be ten years ago. The question is how we can find the suitable man for the job.四、需使用虚拟语气的表语从句在advice, suggestion, order, proposal等表示建议、劝告、命令等含义的名词后的表语从句中，谓语动词需用“should +动词原形”，sho
7、uld可省略。如： My suggestion is that we (should) start early tomorrow.【即学即练】I. 用正确的连接词填空。1. _ I cant understand is _ people keep leaving the door open.2. It is true _ Tony has bought a big house, but _ he got so much money is not known.3. _ will teach us English next term has not been decided yet.4. _ th
8、e new railway station will be ready is unknown.5. My first question was _ the teacher had arrived.6. The most important thing is _ we should make a good study plan.II. 根据括号内所给的汉语提示补全下列句子。1. _ (很遗憾) our basketball team didnt win the match last night.2. _ (很明显) Mr. Green is satisfied with the results
9、of the examination.3. _ (对我来说好像) the only way to solve this problem is to share our ideas.4. _ (我发现很有趣) people buy expensive cars and sit in traffic jams for hours without moving.III. 用that / what / when / whether / because补全下面对话。Lucy: Why are you looking so happy?Jenny: Ive just attended a lecture.
10、 1. _ the speaker said made me excited.Lucy: What was it about?Jenny: About health. It seems 2. _ a lot of people dont know how to keep healthy.Lucy: Quite right. How to get healthy is 3. _ Im concerned about at the moment. But what should I do?Jenny: 4. _ you will stay healthy depends on two factor
11、s exercise and diet.Lucy: You know I always do some running on the road every night.Jenny: Whether you take exercise is one thing, but 5. _ you take exercise is quite another. You shouldnt run at night because it will affect your sleep. Besides, the road isnt a good place for your running. Thats 6.
12、_ theres a lot of traffic, and its too dangerous. You should run in the park instead.Lucy: I see. My plan is 7. _ I will run in the park every morning.Jenny: Great. Also, you must be careful with your diet. Its well-known that we are 8. _ we eat. So you should eat more vegetables.Lucy: Youre right. 参考答案【即学即练】I. 1. What; why 2. that; how 3. Who 4. When 5. whether 6. thatII. 1. Its a great pity that 2. Its clear that 3. It seems to me that 4. I find it amusing thatIII. 1. What2. that 3. What 4. Whether 5. when 6. because 7. that 8. what