高中英语语法讲解与练习之名词性从句.doc

高中英语语法之名词性从句
在句子中起名词作用的句子叫名词性从句 (Noun Clauses）。 名词性从句的功能相当于名词词组, 它在复合句中能担任主语、宾语、表语、同位语、介词宾语等，因此根据它在句中不同的语法功能，名词性从句又可分别称为主语从句、宾语从句、表语从句和同位语从句。
一、引导名词性从句的连接词
引导名词性从句的连接词可分为三类：
连词：that（无任何词意）whether,if（均表示“是否”表明从句内容的不确定性）as if ,as though（均表示“好像”，“似乎”）以上在从句中均不充当任何成分
连接代词：what, whatever, who, whoever, whom,whose, whichever,whomever
连接副词：when, where, how, why,how many,how much,how often
不可省略的连词：
1. 介词后的连词
2. 引导主语从句和同位语从句的连词不可省略。
That she was chosen made us very happy. We heard the news that our team had won.
比较：whether与if 均为"是否"的意思。 但在下列情况下，只可用whether：
1. whether引导主语从句并在句首2. 引导表语从句 3. whether从句作介词宾语4. 从句后有"or not"
Whether he will come is not clear.
大部分连接词引导的主语从句都可以置于句末，用 it充当形式主语。
It is not important who will go. It is still unknown which team will win the match.
二. 主语从句
1、作句子主语的从句叫主语从句。主语从句通常由从属连词that，whether，if和连接代词what，who，which，whatever，whoever以及连接副词how，when，where，why等词引导。that在句中无词义，只起连接作用；连接代词和连接副词在句中既保留自己的疑问含义、又起连接作用，在从句中充当从句的成分。例如：
What he wants to tell us is not clear. 他要跟我们说什么，还不清楚。
Who will win the match is still unknown. 谁能赢得这场比赛还不得而知。
It is known to us how he became a writer. 我们都知道他是如何成为一名作家的。
Where the English evening will be held has not yet been announced. 英语晚会将在哪里举行，还没有宣布。
有时为避免句子头重脚轻，常用形式主语it代替主语从句作形式主语放于句首，而把主语从句置于句末。主语从句后的谓语动词一般用单数形式。常用句型如下：
（1） It + be + 名词 + that从句（2）It + be + 形容词 + that从句（3）It + be + 动词的过去分词 + that从句（4）It + 不及物动词 + that 从句
另注意在主语从句中用来表示惊奇、不相信、惋惜、理应如此等语气时，谓语动词要用虚拟语气“(should) +do”，常用的句型有：It is necessary (important, natural, strange, etc.) that … It is suggested (requested, proposed, desired, etc.) that…
2、第一部分：常规主语从句，即句子在复合句中充当一个主语
主语从句的时态：不受主句的时态影响和限制。
（1）That he finished writing the composition in such a short time surprised us all.
（2）Whether we will go for an outing tomorrow remains unknown.
（3）Who will be our monitor hasn't been decided yet.
（4） Whom we must study for is a question of great importance.
（5）What caused the accident remains unknown.
（6）Whatever you did is right.
（7）Who the watch belongs to was lost is unknown.
（8）What we need is time.
（9）What we need are good doctors.
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三单,但也有例外,如例9
第二部分：为了防止句子头重脚轻，通常把形式主语it放在主语位置，真正主语搁置于句末
（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 he should do that.
（5）It is important that we all should attend the meeting.
（6）It is strange that the man should have stuck to his silly ideas.
（7）It is a pity that we won't be able to go to the south to spend our summer vacation.
（8）It is still a mystery what caused the accident.
（9）It is said that he has gone to shanghai.(=He is said to have gone to shanghai)
（10）It is known to all that the gun powder was first invented by the Chinese.
（11）It is suggested that the work should be done with great care.
（12）It seems that he has seen the film.(=He seems to have seen the film)
（13）It happened that the two cheats were there. (=The two cheats happened to be there)
小结:（1)以that 引出的主语从句,常以形式主语it引导. 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)例句4,5,6,11.
3、主语从句的用法
主语从句是在复合句中充当主语的从句，通常放在主句谓语动词之前或由形式主语it代替，而本身放在句子末尾。
1. It 作形式主语和it引导强调句的比较
It 作形式主语代替主语从句，主要是为了平衡句子结构，主语从句的连接词没有变化。而it引导的强调句则是对句子某一部分进行强调，无论强调的是什么成分，都可用连词that。被强调部分指人是也可用who/whom。例如： It is a pity that you didn’t go to see the film.
2. 用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 that… 很自然… It is strange that… 奇怪的是…
(3) it ＋不及物动词＋从句
It seems that… 似乎… It happened that… 碰巧…
(4) it is＋过去分词＋从句
It is reported that… 据报道… It has been proved that… 已证实…
3. 主语从句不可位于句首的五种情况
(1) if 引导的主语从句不可居于复合句句首。
(2) It is said , (reported) …结构中的主语从句不可提前。例如：
It is said that President Jingo will visit our school next week.
(3) It happens…, It occurs… 结构中的主语从句不可提前。例如：
It occurred to him that he failed in the examination.
(4) It doesn’t matter how/whether …结构中的主语从句不可提前。例如：
It doesn’t matter whether he is wrong or not.
(5) 含主语从句的复合句是疑问句时，主语从句不可提前。例如：
Is it likely that it will rain in the evening?
4. 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，而that 则不然。例如： What you said yesterday is right.
三、宾语从句
名词句用作宾语的从句叫宾语从句。引导宾语从句的关联词与引导主语从句表语从句的关联词大致一样，在句中可以作谓语动词或介词及非谓语动词的宾语。
1. 由连接词that引导的宾语从句
由连接词that引导宾语从句时，that在句中不担任任何成分，在口语或非正式的文体中常被省去，但如从句是并列句时,第二个分句前的that不可省。例如：
He has told me that he will go to Shanghai tomorrow. 他已经告诉我他明天要去上海。
We must never think (that) we are good in everything while others are good in nothing. 我们决不能认为自己什么都好，别人什么都不好。
注意：在demand、order、suggest、decide、insist, desire, request, command等表示要求、命令、建议、决定等意义的动词后，宾语从句常用“（should）+ 动词原形”。例如：
I insist that she (should) do her work alone. 我坚持要她自己工作。
The commander ordered that troops (should) set off at once. 司令员命令部队马上出发。
2. 用who，whom, which, whose, what, when, where, why, how, whoever, whatever, whichever等关联词引导的宾语从句相当于特殊疑问句，应注意句子语序要用陈述语序。例如：I want to know what he has told you. 我想知道他告诉了你什么。
She always thinks of how she can work well. 她总是在想怎样能把工作做好。
She will give whoever needs help a warm support. 凡需要帮助的人，她都会给予热情的支持。
3. 用whether或if引导的宾语从句，其主语和谓语的顺序也不能颠倒，仍保持陈述句语序。此外，whether与if 在作“是否”的意思讲时在下列情况下一般只能用whether，不用if：
a. 引导主语从句并在句首时；b. 引导表语从句时；c . 引导从句作介词宾语时；d. 从句后有“or not”时；e. 后接动词不定式时。例如：
Whether there is life on the moon is an interesting question. 月球上有没有生命是个有趣的问题。 The question is whether she should have a low opinion of the test?现在的问题是她是否应该有一个低意见的测试？ Everything depends on whether we have enough money. 一切要看我们是否有足够的钱。 I wonder whether he will come or not. 我想知道他来还是不来。 Can you tell me whether to go or to stay? 你能否告诉我是去还是留？
4. 注意宾语从句中的时态呼应，当主句动词是现在时，从句根据自身的句子情况，而使用不同时态。例如：
he studies English every day. （从句用一般现在时）
he studied English last term. （从句用一般过去时）
I know (that) he will study English next year. （从句用一般将来时）
he has studied English since 1998. （从句用现在完成时）
当主句动词是过去时态（could, would除外），从句则要用相应的过去时态，如一般过去时，过去进行时，过去将来时等；当从句表示的是客观真理，科学原理，自然现象，则从句仍用现在时态。例如：The teacher told us that Tom had left us for America．
5. think, believe, imagine, suppose等等动词引起的否定性宾语从句中，要把上述主句中的动词变为否定式。即将从句中的否定形式移到主句中。例如：
We don’t think you are here. 我们认为你不在这。
I don’t believe he will do so. 我相信他不会这样做。
6.时态：1.主句用一般现在时，从句可用任意时态。2.主句用过去时，从句用过去某个时态。
3.主句用过去时，从句是客观真理时，只用一般现在时。
7.宾语从句的连接词
从属连词：连接宾语从句的从属连词主要有that,if,whether.that引导表示陈述句的宾语从句,而if和whether引导表示“是否”的宾语从句.
He told me that he would go to the college the next year他告诉我他明年上大学.
I don’t know if there will be a bus any more.我不知道是否还会有公交车.
Nobody knew whether he could pass the exam.没人知道他是否会通过考试.
连接代词：连接代词主要有who, whom ,whose ,what ,whoever ,whomever ,whosever, whatever, whichever等.连接代词一般指疑问,但what, whatever除了指疑问外,也可以指陈述.
Do you know who has won Red Alert game? 你知道是谁赢得了红色警报的游戏？
The book will show you what the best CEOs should know.
这本书会告诉你最好的执行总裁该了解些什么.
Have you determined whichever you should buy,a Motorola or Nokia cell phone?
你决定好是买诺基亚还是摩托罗拉的电话了吗?
连接副词：连接副词主要有when,where,why,how,whenever,wherever,however等.
He didn’t tell me when we should meet again.他没有告诉我什么时候我们能再见面.
Could you please tell me how you use the new panel?你能告诉我怎么用这个新的操作盘吗?
None of us knows where these new parts can be bought.
没有人知道这些的新的零件能在哪里买到.
8.动词的宾语从句
大多数动词都可以带宾语从句
We all expect that they will win , for members of their team are stronger.
我们都预料他们会赢,因为他们的队员更强壮.
He told us that they would help us though the whole work.
他告诉我们在整个工作中,他都会帮忙的.
部分“动词+副词”结构也可以带宾语从句
I have found out that all the tickets for the concert have been sold out.
我发现这场音乐会的所有票都卖光了.
Can you work out how much we will spend during the trip?
你能计算出这次旅行我们将花费多少钱吗?
动词短语也可以带宾语从句
常见的这些词有:make sure确保 make up one’s mind下决心 keep in mind牢记
Make sure that there are no mistakes in your papers before you turn them in.
在上交试卷前确保没有任何错误.
可运用形式宾语it代替的宾语从句
①动词find,feel,consider,make,believe等后面有宾语补足语的时候,则需要用it做形式宾语而将that宾语从句后置.
I think it necessary that we take plenty of hot water every day .我认为每天多喝开水是有必要的.
I feel it a pity that I haven’t been to the get-together.　我没去聚会,感觉非常遗憾.
I have made it a rule that I keep diaries. 　我每天写日记成了习惯.
We all find it important that we (should) make a quick decision about this mater.
我们都认为对这件事马上做出决定很重要.
②有些动词带宾语从句时需要在宾语与从句前加it
这类动词主要有:hate, take , owe, have, see to.
I hate it when they with their mouths full of food.我讨厌他们满嘴食物时说话.
He will have it that our plan is really practical.他会认为我们的计划确实可行.
We take it that you will agree with us.我们认为你会同意我们的.
When you start the engine, you must see to it that car is in neutral.
开启发动机时, 一定要使汽车的离合器处于空挡位置.
③若宾语从句是wh-类,则不可用it代替
We all consider what you said to be unbelievable.我们都认为你所说的是不可信的.
We discovered what we had learned to be valuable.我们发现我们所学到的东西都是有用的.
9.介词的宾语从句
用wh-类的介词宾语从句
We are talking about whether we admit students into our club.
我们正在讨论是否让学生加入我们的俱乐部.
The new book is about how Shenzhou 6 manned spaceship was sent up into space.
这本新书是关于神州6号载人航天飞船是如何升入太空的.
用that,if引导的介词宾语从句
有时候except,but,besides三个介词后可见到that引导的宾语从句
I know nothing about my new neighbor except that he used to work with a company.
对于我的新邻居我只知道他曾在一家公司上班,其他一无所知.
10.形容词的宾语从句
常用来引导宾语从句的形容词有: sure,certain,glad,please,happy,sorry,afraid,satisfied,surprised
I am sure I will pass the exam.我确信我会通过考试.
I am sorry that I have troubled you so long.很抱歉我这么长时间在打扰你.
He is glad that Li Ming went to see him when he was ill.
他很高兴在他生病的时候李明能去看望他.
11.if,whether在宾语从句中的区别
① if和whether在作“是否”解时,引导宾语从句常放在动词know,ask,care,wonder,find out等之后,介词后一般不用if② 少数动词,如:leave,put,discuss,doubt后的宾语从句常用whether.③ whether后可以加or not,但是if不可以.④ 在不定式前只能用whether.（如：I can’t decide whether to stay. 我不能决定是否留下。）⑤ 避免歧异时,我们常用whether而不用if.
12.哪些宾语从句不可以省略引导词that
1.当that作learn,suggest,explain,agree,wonder,prove,mean,state,feel,hold等动词的宾语时;2.当宾语从句较长时;3.当主语状语置于主句尾,宾语从句之前时;4.当主语谓语动词(包括非谓语动词)与宾语从句之间有插入语时;5.当一个动词带有两个或两个以上宾语从句时,此时第一个that可以省略,第二个that不可以省略;6.当宾语从句中的主语是this,that或this,that做主语的定语时;7.当宾语从句是双宾语中的直接宾语时;当宾语从句的主语是非谓语动词或主语从句时;8.当主语中的谓语动词是固定词组时;9.当宾语从句有it做其先行词时;10.在直接引语中,转述分句把宾语从句隔开时.
13.宾语从句的否定转移
主句的谓语动词是think,believe,imagine,suppose,consider,espect,fancy,guess等,并且主句的主语是第一人称而且为一般现在时,从句的否定词一般要转移到主句上来,其反义疑问句一般与宾语从句一致.
I don’t think he will come to my party.而不能说成I think he won’t come to my party.
我认为他不会来我的舞会.
I don’t believe that man is killed by Jim,is he?
我认为那个人不是Jim所杀的,是不是?
如果宾语从句中有某个含有否定意义的形容词或副词,其反义疑问句要用肯定形式.
We find that he never listens to the teacher carefully,does he?
我们发现他从来不仔细听老师讲课,是不是?
14.宾语从句的时态和语序
当主句为现在时或将来时,宾语从句的时态一般不受主句的时态所影响.
当主句为过去时
①从句用一般过去时或过去进行时表示与主句谓语动词动作同时发生
I only knew he was studying in a western country,but I didn’t know what country he was in.
我只知道他当时在西方的一个国家读书,可不知道是哪个国家.
He asked me if I was reading the story The Old Man and the Sea when he was in.
他问我他进来的时候我是否正在读<<老人与海>>.
②从句过去完成时表示该动作发生在主句谓语动作之前
He told me that he had told Mary about the meeting already.
他告诉我他已经把有关会议的事情告诉的了Mary.
③从句谓语用过去将来时表示该动作发生在主句谓语动作之后
The reporter asked if the government would take necessary measures to put down the to-do.
记者问政府是否会采取必要的措施镇压骚乱.
如果从句是一个客观真理,那么从句的时态不根据主句的时态而变化
The teacher said that the moon goes around the earth yesterday.
老师昨天说月亮绕着地球转.
当宾语从句的引导词是who,which,what,when,where,how,why等表疑问时,不能按正常语序安排,经常将这类引导词置于句首
Who do you think the public might choose as their favorite singer this year?
你认为今年公众会选谁为他们最喜欢的歌手.
四、表语从句
1、在句中作表语的从句叫表语从句。引导表语从句的关联词与引导主语从句的关联词大致一样，表语从句位于连系动词后，有时用as if引导。其基本结构为：主语 + 系动词 + that从句。例如：
The fact is that we have lost the game. 事实是我们已经输了这场比赛。
That’s just what I want. 这正是我想要的。
This is where our problem lies. 这就是我们的问题所在。
That is why he didn’t come to the meeting. 那就是他为什么不到会的原因。
It looks as if it is going to rain. 看上去天要下雨了。
需要注意的，当主语是reason时，表语从句要用that引导而不是because。例如：
The reason why he was late was that he missed the train by one minute this morning .
【注意】whether 可引导表语从句，但与之同义的if却通常不用于引导表语从句。
2、简介
定义：A 表语从句就是用一个句子作为表语。说明主语是什么或者怎么[1]样，由名词、形容词或相当于名词或形容词的词或短语充当，和连系动词一起构成谓语。
The problem is puzzling. 这问题令人困惑
主语 连系动词 形容词作表语
The problem is when we can get a pay rise. 问题是什么时候我们可以得到加薪.
主语 连系动词 一个句子作表语---表语从句
B 连接表语从句的连接词有：that, what, who, when, where, which, why, whether,how.
He has become a teacher. 他已经成为一名教师。
He has become what he wanted to be ten years ago. 他已经成为了他10年前想成为的。
She has remained there for an hour. 她曾在那里停留了一个小时。
She has remained where I stood yesterday for an hour.她一直在我昨天站的地方站了一个小时。
His suggestion is good. 他的建议是好的。
His suggestion is that we should stay calm. 他的建议是，我们应该保持冷静。
The question is confusing. 这个问题令人困惑.
The question is when he can arrive at the hotel. 问题是，他什么时候可以到达酒店。
who will travel with me to Beijing tomorrow.谁与我明天将前往北京。
why he cried yesterday. 昨天他为什么哭。
how I can persuade her to join us in the party. 我怎么能说服她加入我们的派对。
whether the enemy is marching towards us. 是否敌人正向我们行进.
注意：
A 表语从句一定要用陈述语序。
False: The question is when can he arrive at the hotel.
Right: The question is when he can arrive at the hotel.
B 不可以用if，而用whether 连接表语从句(as if 例外）。
引导宾语从句时可以互换if/whether 位于介词后要用whether
位于句首时要用whether
引导表语从句，主语从句，同位语从句时要用whether
False: The question is if the enemy is marching towards us.
Right: The question is whether the enemy is marching towards us.
Right: It looked as if he had understood this question.
C 不像宾语从句，在有表语从句的复合句中，主句时态和从句时态可以不一致。
Right: The question is who will travel with me to Beijing tomorrow.
Right: The question is why he cried yesterday.
D that在表语从句中不可以省掉。
3、基本用法
表语从句只能置于主句之后，而主句的动词只能是联系动词。
名词性从句在be等系动词后作表语时被称为表语从句， 例如： The problem is how we can get the things we need.问题是我们怎样能弄到我们需要的东西。(how 在表语从句中充当方式状语)// The scissors are not what I need. 这把剪刀不是我所需要的。(what 在表语从句中充当宾语)// What I told him was that I would find him a good play. 我告诉他的是我会给他找个好剧本。(what在主语从句中作直接宾语， that作为表语从句的引导词在该表语从句中不充当句子成分， 不能省略)// That is what I want to tell you.那就是我想要对你讲的。(what在表语从句中充当直接宾语)// That is why she failed to pass the exam. 那就是她考试不及格的原因。(why 在表语从句中充当原因状语)
注意： “That is why...”是常用句型， 意为“这就是……的原因/因此……”， 其中why引导的名词性从句在句中作表语， 该句型通常用于针对前面已经说明过的原因进行总结， 又如： That is why you see this old woman before you know, Jeanne. 珍妮， 这就是现在这个老太婆出现在你面前的原因。(前文提到Jeanne对老妇人显得苍老憔悴深感诧异， 说话人对她讲述了其中的原因之后，用这一句来进行概括)。// That is why I came. 这就是我来的原因。
下面是两个与“That is why...”形式相似的结构， 它们与“That is why...”结构之间的关系要能够辨析清楚：
(1)“That is why...”与“That is the reason why...”同义， 只不过从语法结构上讲， “That is the reason why...”中why引导的是—个定语从句， 将其中的the reason去掉则与“That is why...”结构一样， 例如： That is (the reason) why I cannot agree. 这就是我不能同意的理由。
(2)“That is because...”句型中从属连词because引导的名词性从句在此作表语， 这也是个常用句型， 意为“这就是为什么……/因为……”。“That is because...”与“That is why...”之间的不同在于“That is because...”指原因或理由， “That is why...”则指由于各种原因所造成的后果， 例如： He did not see the film last night. That is because he had to help his little sister with her homework.昨天晚上他没有去看电影， 那是因为他得帮助他的妹妹做作业。(第一句话说明结果， 第二句话说明原因)
He had seen the film before. That is why he did not