专题三名词性从句.doc

专题三 名词性从句
一、定义：
(1) 名词性从句：在句子中起名词作用的从句叫做名词性从句。它包括主语从句, 表语从句, 宾语从句和同位语从句。
(2) 连接词：引导名词性从句的连词。有连接代词what, whatever, who, whoever, whom, which, whichever, whose (有词义，在从句中充当成分，作主语、宾语、表语或定语)；连接副词when, where, how, why (有词义，在从句中充当成分，作状语)；从属连词that, if, whether, as if (除that外，都有词义，在从句中不充当任何成分)。
二、做题步骤：
1. 通过从句是否在整个句子中起名词的作用确定从句的类型。
2. 针对从句本身进行分析，看从句是否缺少主语、宾语、表语或定语等句子成分，如有缺失，则用相应的连接代词。
3. 如果从句中不缺少上述成分，则根据句意是否完整用相应的连接副词或有词义的从属连词。
4. 从句的成分和句意都无问题，则用that起连接作用。
(1)______ was most important to her, she told me, was her family.
A. It B. This C. What D. As
(2)It is obvious to the students ______ they should get well prepared for their future.
A. as B. which C. whether D. that
(3)—I prefer shutting myself in and listening to music all day on Sundays.
—That’s ______ I don’t agree. You should have a more active life.
A. where B. how C. when D. what
三、考点：
1. 主语从句：在句子中做主语, 它可以放在主句谓语动词之前, 但that引导的主语从句多数情况由it做形式主语, 而把主语从句放在主句之后：
e.g. who did that is known to all. It is interesting that you should like him.
一般情况下, 从句做主语, 谓语用单数。但what引导的主语从句，谓语动词视情况而定: e.g. What I need most are books. What he wants is a book. What I need is time.
常见用it作形式主语的句型结构有：
(1) It is + n. + that clause
* It is a fact (a shame;a pity;an honor;no wonder;good news) +that clause
e.g. It’s a pity that he won’t come.
(2) It is + adj. + that clause
* It is necessary(strange;important;wonderful;possible;likely)+that+主语+ (should)+v.原形
e.g. It is strange that you should like him.
(3) It is + done + that clause * It is said;reported;believed;decided...+that clause
e.g. It is said that Bell invented the telephone.
(4) It + vi./vt. + O + that-clause
* It seems;happened;doesn’t matter;has turned out;make a difference(to sb.)…+that clause
e.g. It happened that I had no money on me. It doesn’t matter what you do.
* It struck sb./ occurred to sb. +that clause
e.g. It never occurred to me that you could succeed in persuading him to change his mind.
2. 表语从句：在从句中做表语,位于主句中系动词之后：
e.g. This is where our problem lies.
表语从句还可以用as if 引导。 e.g. It looks as if it is going to rain.
* The reason (why…/for…) is that…
e.g. The reason why he is late for school is that he missed the early bus.
* That’s because (原因)... * That’s why (结果)...
e.g. That’s because he missed the early bus.
e.g. That’s why he didn’t come to the meeting.
* The truth/trouble/problem/question is that…
e.g. The question is who can complete the difficult task.
3. 同位语从句：它通常跟在名词后面, 进一步说明该名词的具体内容。引导同位语从句的名词主要有：fact, idea, hope, order, promise, word, question, belief, news, truth, suggestion, thought, problem, doubt, information, condition等,一般用that引导。
e.g. The news that our team has won the match is true.
Word came that our team won the match.
4. 宾语从句：在句中做及物动词或介词宾语。
e.g. We can learn what we did not know. She always thinks of how she can work well.
(1) 如果主句的谓语动词是及物动词think, consider, believe, make, feel, find等，则把宾语从句置于宾语补足语之后，用it做形式宾语。
e.g. We find it necessary that we practise spoken-English every day.
(2) 另外某些做表语的形容词如: sure, happy, glad, certain等之后也可以用宾语从句。
e.g. I am sure that he will succeed.
(3) 在like, dislike, enjoy, love, hate, prefer, appreciate等词后跟宾语从句时，需用形式宾语it. e.g. I hate it when people talk with their mouths full.
I like it that everyone passed the exam.
I’d appreciate it very much if you could reply soon.
(4) that从句除可放于except, but, in之后外，通常不作介词的宾语从句，而且此时的that不能省略。
e.g. I know nothing about him except that he is from the south.
This is an ideal site for a university in that it is far from the downtown area.
(5) 由动词和介词构成的动词短语，动词后接宾语从句时，要用it 作形式宾语。
e.g. I’ll see to it that he is taken good care of when you are absent.
I just took it for granted that he’d always be around.
Keep it in mind that you have to be home by ten o’clock.
(6) that引导宾语从句不可省略的情况：一个句子有多个并列的宾语从句时，从第二个开始不可省略。 e.g. He said (that) you needn’t worry and that he would help you.
注：谓语动词和that从句间有插入语时，that不可省略。
e.g. We decide, as he suggested, that we will set out early tomorrow.
(7) 感叹句性的宾语从句：
e.g. Parents are taught to understand how important education is to their children’s future.
I was surprised by her words, which made me recognize what silly mistakes I had made.
* It is uncertain ______ side effect the medicine will bring about, although about two thousand patients have taken it.
A. that B. what C. how D. whether
(8) 在“一个坚持要求，两个命令，四个建议，四个要求”后等意义的动词后的宾语从句中须用(should) + v.原形。
e.g. The mother insisted that the boy (should) be back before 10 o’clock.
The doctor ordered that she (should) stay in bed for a few days.
We suggested that we (should) have a meeting.
He demanded that we (should) start right away.
(9) 宾语从句中的时态：当主句用一般现在时态时，从句根据自身的情况可使用不同的时态；但当主句用一般过去时态时，从句则要用相应的过去时态。（从句表示的是客观真理，科学原理，自然现象时，仍用一般现在时态）
e.g. I know (that) he will study English next year.
She says she cleaned the floor.
He said (that) he was very glad.
The teacher told us (that) the earth is round.
(10) 宾语从句的语序问题：
1）. 双重疑问句：否定前移的动词(think, believe, suppose, imagine, expect, guess等)后接特殊疑问词引导的宾语从句时,语序为特殊疑问词位于句首, 主句变成一般疑问句, 后面是陈述句。
e.g. Who do you think is the best singer in your school? Why do you think he was late?
2）. 特殊疑问词who, whom, what, which, whose, where, when, where, how等引导的宾语从句，应为特殊疑问词加上陈述句语序。
e.g. He asked where Mr. Wang was. I want to know what he has told you.
但What’s the matter with sb.? 和What’s wrong with sb.? 除外
e.g. —What’s the matter with you?
—What did she say?
—She asked what was the matter with me.
四、连接词的用法：
1. what与whatever
两者都可以引导名词性从句，但whatever比what的语气强，意为 “anything that(任何事物)”。
e.g. What she did was right. Whatever she did was right.
2. who与whoever
who常保留本身疑问的含义，表特指，即“谁”，整个从句侧重指整体的事件；whoever表泛指，意为the person who...或anyone who...，即“无论谁”，整个从句侧重指人。
e.g. Who broke the window is unknown.
Whoever(Anyone who) breaks the law will be punished.
Whoever(The person who) told you about it was lying.
Who will go with us has not yet been decided.
* Could I speak to ______ is in charge of International Sales please?
A. who B. what C. whoever D. whatever
3. if 与whether
(1) if、whether均可使用的情况：引导动词的宾语从句时
e.g. I wonder if /whether the news is true.
(2) 只能用if的情况：动词的宾语从句，而且宾语从句部分是否定句时
e.g. He considered if he couldn’t tell her the secret. 他考虑是否不应该把秘密告诉她。
I don’t care if it doesn’t rain. 我根本不在乎不下雨。
(3) 习惯用whether的情况：
a. 在主语从句、表语从句和同位语从句中
e.g. The question is whether the film is worth seeing.
The news whether our team has won the match is unknown.
Whether we shall attend the meeting hasn’t been decided yet.
b. 在介词后 e.g. It all depends on whether they will support us.
c. 后面直接跟动词不定式时 e.g. He doesn’t know whether to stay or not.
d. 与or或or not连用 e.g. We didn’t know whether or not she was ready.
e. 动词的宾语从句在句首时 e.g. Whether this is true or not, I can’t say.
(f. 引导一个让步状语从句，表“不管” e.g. Whether he agrees or not, I shall do that.)
注：doubt的用法：若doubt 做“怀疑”解释接宾语从句时，主句为肯定句用whether或if，主句为否定句或疑问句用that。 e.g. I doubt whether/if he will come soon.
e.g. I do not doubt that he will come soon. Do you doubt that he will come soon?
e.g. There is no doubt that he will come soon.(同位语从句)
4. what的惯用句式：A is to B what C is to D. “A对B之关系犹如C对D之关系”
e.g. Air is to us what water is to fish.
What salt is to the food, wit and humor are to conversation and literature.
隽语与幽默之于会话与文学，恰像盐之于食物一样。
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