名词从句学习指要，本文主要内容关键词为：从句论文,名词论文，此文献不代表本站观点，内容供学术参考，文章仅供参考阅读下载。
根据性质，从句大致分为名词性从句、形容词性从句（即句法角度而言的定语从句）和副词性从句（即状语从句）。这三类从句中，以名词性从句的形式最为丰富，这是由名词在句中的语法功能所决定的。顾名思义，名词从句的句法功能如同名词一样，在句中可充当主语、宾语（包括介词宾语和动词宾语以及某些形容词后的宾语）、表语和同位语。据此，所谓名词从句，即主语从句、表语从句、同位语从句和宾语从句。
（一）主语从句
Ⅰ．语序问题：
主语从句在复合句中作主语，其位置与陈述句基本结构中的主语相同。换言之，名词从句（当然包括主语从句）的语序均为陈述句语序，不能使用疑问句语序。例如：
汉语：他所做的对我有很大的帮助。
误：What does he do helps me a lot.
正：What he does helps me a lot.
析：名词性从句的语序用陈述句语序，即使从句含有表示疑问意义的关联词也如此。
Ⅱ．连接词的种类及其用法要点
主语从句的连接词有：
Ⅲ．主语从句连接词用法要点
1.从属连词 that
(1)that本身无词义，不作句子成分，但不可省略。
That he will be here at 11 is certain.
主语从句中常用it作形式主语而将主语从句后置，以示强调或使句子衡。
That the earth is round is obvious.(=It is obvious that the earth is round.)
(2)在It seems(appears,happens,occurs等）之后，主语从句的后置是不可改变的。
It seems to me that your advice is good.
It happened that he was out.
It suddenly occured to me that I had left my key in the office.
(3)在"It is (was)wrong(right,better,essential,important,necessary,strange,natural等）之后主语从句常用虚拟语气，即“should＋动词原形”，should也可省去。
It is necessary that they(should)act at once.
在“It is (was)＋名词短语”后，主语从句后置已成习惯。
It is a pity that you can't come.
(4)在以“It＋be＋过去分词”开始的句子里，主语从句后置更为常见。
It is known that the compass was invented by the Chinese.
It was decided that they would meet in Beijing.
It was arranged that the students would go there on foot.
(5)当that引导的主语从句用于疑问句中时，要用it作形式主语而把主语从句后置。
How is it that you are late?你怎么迟到了？
Does it matter much that he will not come?他不来关系大吗？
2.连词whether
Whether we shall go or stay is uncertain.
(=It is uncertain whether we shall go or stay.)
由whether引导的主语从句可置于句首。
3.疑问代词who,whom,whose,which疑问副词when,where,why,how
Who came to see us remained unknown.
How he did it is still a mystery.
Why he did it does not concern us.
Ⅳ．值得注意的问题
1.关系代词what,whatever,whoever,whichever等引导主语从句时，不能换成带形式主语it的结构。
What he said is true.
Whoever comes is welcome.
Whichever of your duties you fulfil will be respected.
2.表示“是否”时，一般用whether引导主从，不用if。
If she will come of not is still a question.（误）
Whether she will come or not is still a question.（正）
3.从句作主语时，主句的谓语动词一般用单数。
What we needs is more time.
Who will go is ont important.
4.主语从句用it作主语的句子不少，有些已成固定说法，并有固定译法。
(1)It is+n.+that…（主语从句）
It is a fact that…事实是……
It is good news that……是好消息。
It's a pity that we can't go there.
It's no surprise that our team(should)have won the game.
(2)It is+adj.+that…（主语从句）
It is possible that…可能
It is clear that…很清楚
It's certain that he'll do well in the exam.
It is probable that he has told her everything.
(3)It is+p.p.+that…
It is well known that…众此周知……
It is reported(recorded)that…据报道（记载）…
It is said that Mr Green arrived at our shcool.
It is thought that Jack drove very badly.
(4)It+seems(happens and other vi.)+that…
It follows that…从而，这样一来，于是……由此可见……
It happened that…碰巧……
It appears that…看起来
It seems that Alice isn't coming to our party at all.
It happend that I was out when you came.
(5)还有其它一些结构的固定译法：
It must be pointed out that…必须指出……
It has been proved that…业已证明……
It turns out that…结果是……
It must be admitted that…必须承认……
It is to be noted that…要注意……
It will be seen from this that…由此可见……
（二）表语从句
Ⅰ．表语从句的语序：
表语从句在复合句中起表语作用，位于连系动词之后，与其一起构成主句的谓语。
Ⅱ．表语从句连接词用法实例：
表语从句的连接词大致与主语从句相同，除此以外，还可用as if,because来引导，请看。
But the fact remains that we are behind the other groups.
The question is whether we can finish the work by tomorrow evening.
This is because the earth is moving round the sun.
It looks as if it is going to rain.
The problem is not who will go but who will stay.
Alice is no longer what she used to be.
The question is which plan is better.
This was just when our League branch was being formed.
This is where the Red Army crossed the Yangtze River.
My question is how we should use the subjuctive mood.
That's why we should start out early tomorrow morning.
Ⅲ．值得注意的问题
1.如主句的主语是名词reason，则表语从句的连词要用that，说明reason的内容表事情发生的原因，常构成“the reason+(wly)定语从句＋从句＋is/was＋that”从句结构。如：
The reason for his being late is that he didn't catch the early bus.
The reason why he was so angry was that he had been laughed at in public.
2.如主句的主语是名词idea,advice,suggestion,order,proposal等名词时，则表语从句的谓语应用虚拟语气，即主语无论是单数或复数，谓语一律用原形动词或“should＋动词原形”的形式。
My idea is that we should stick to our plan.
My friend's advice is that I should give up smoking.
My suggestion is that we should go by bus instead of by train.
3.连词whether和if虽都可作“是否”解，但if不能引导表语从句。
The problem is whether（不能用if）we can catch up with the advanced countries before the year 2000.
4.连接词that没任何词义，从句中不作句子成分，口语中常可省略。
My idea is (that)you'd better go with us.
5.注意连词why,how,where以及because引导表语从句的译法：
①why引导表语从句时，意思是“……的原因”，常用来叙述事情的结果。这时主句的主语常是that或this。that或this所替代的前文内容常解释了why从句的原因，why引导的表语从句说明在此原因下导致事情的结果，即“前因后果”。
Ten years of hard work!That's why I now look so old.
十年辛苦的劳动！这就是我现在显得如此苍老的原因。
析：that指代"Ten years of hard work"，表示事情的起因，why从句表示在此因情况下导致的结果"I now look so old"。
That is why she was absent yesterday.那就是她缺席的原因。
②This is how I lost my bike.我的自行车就是这样丢的。
③That is where we first met.那就是我们初次相会的地方。
④because引导表语从句常用来说明某种结果所产生的原因，即“前果后因”。这时主句部分也常用that,this来指代前文的结果。
Every year,tobacco companies must persuade new people to start smoking cigarettes.This is because each year millions of smokers die from the habit.每年烟草公司要设法使一些不吸烟的人开始吸烟，这是因为每年数以百万计的烟民因吸烟死去了。
析：this指代前文"tobacco companies must persuade new people to start smoking cigarettes"这一结果，because从句说明了这一结果所产生原因。
6.what引导主语从句表示结果时，其后的表语从句需用that引导，来解释、说明事情的原因。
What cost him his life was that he was too careless.
使他丧命的原因是他太粗心了。
尚须说明：在what引导的名词性从句中，what有两种意思：一是作“什么”讲，保留疑问代词的询问意义；二是作“所……的人（事，东西）”讲，相当于“the thing which…"。在表语从句中也是如此。
That is what thay have done for the revolution.
7.从疑问词引导的名词性从句中，虽然这些疑问词仍保留疑问意义，但一定要注意从句用陈述句的语序。表语从句中也是如此。
My question is when we can finish the work.
（三）同位语从句
Ⅰ．引导词的选择：
同位语从句在句中起同位作用，一般跟在某些名词如：idea,news,fact,promise,doubt,question,hope,reason,truth,result,order,suggestion…后面，用以说明名词所表示的具体内容，这些名词叫做同位语。引导词可有：what,whether,how,when,where,why,who,which等。例如：
1.We expresss the hope that they would come to visit China anain.我们表示希望他们再来中国访问。
2.I have no idea when she will be back.我不知道她什么时候回来。
3.There is no doubt that the price of cars will bring down.毫无疑问，汽车的价格会下降的。
4.You have no idea how worried I was!你不知道我有多着急！
5.The question how the students could improve their spoken English is very important.学生如何才能改进他们的口语，这个问题很重要。
Ⅱ．几点注意事项：
1.当同位语从句的主句的谓语部分过短时，可以把谓语动词提前，使同位语从句与名词分开，成为分隔式，以避免头重脚轻。如：
Word came that China has already joined the WTO.有消息传来，中国已经入关了。
An order has come from Berlin that no language but German may be taught in the schools.从柏林传来命令说学校里中能教德语。
2.引导同位语从句的that无词义，不充当句子成分，不可用which替代。
The news that he has been defeated in the election is not true.（that只起连接作用）
3.同位语从句的谓语动词形式和宾语从句的谓语动词形式一样受主句时态影响，但如果同位语从句是客观事实、普遍真理时，也必须用一般现在时。如：
In the 16th century,Magellen's men found out the truth that the earth is round.在十六世纪，麦哲伦的海员们就弄清了地球是圆的这一真理。
4.如果某些动词后宾语从句要用should型的虚拟语气的话，那么其同源名词引起的同位语从句也要用虚拟语气。如：demand,suggestion.等。如：
My suggestion that we (should) build another library in our school was discussed at the meeting.我们应再建一个图书馆，我的这个建议在会上广泛地讨论了。
Ⅲ．同位语从句与定语从句的区别：
1.同位语从句一般跟在某些抽象名词的后面，如belief,fact,hope,idea,news等，用以说明或解释前面的名词；而定语从句一般跟在具体名词后面，起修饰作用。即限定它前面的名词的范围或补充。
2.同位语从句用that开头，这个that是连词，只起连接作用，不充当句子成分作用，一般不能省略；而定语从句中的that，在从句中起主语，宾语或表语的作用。充当宾语时可以省略，关系副词充当从句中的状语。如：
①The news that he told me yesterday is very exciting.（定语从句that作told的直宾）
②The news that the teacher would show us a movie excited all of us.（同位语从句that在从句中不作任何成分）
③Yesterday we visited the house where Lu Xun once lived.（定语从句，where在从句中作地点状语）
3.引导定语从句的when,where,why,how是关系副词，不但在从句中充当成分，还有与其含义相当的先行词，如when的相应先行词是表示时间的句词，where的相应先行词是表示地点的名词，why的相应先行词是表示原因的名词。而引导同位语从句的when,where,why,how是连接副词，虽可以在从句中充当状语成分，但与先行词意义上无联系。
例如：I'll never forget the days when we were together.（定语从句，先行词the days与关系副词when构成含义上相当的搭配关系，when=on which）
I have on idea when he will be back.（同位语从句，名词idea与连接副词when在含义上没有任何搭配关系）。
再比较：
The office where(=in which)you work is here.（定语从句）你工作的办公室在这儿。
Then arose the question where we were to get so much money.（同位语从句）接着我们提出从哪里弄这么多钱的问题。
The reason why(=for which)he did not come is quite clear.（定语从句）他为什么不来的理由是很明显的。
Xiao Wang has solved the problem why the TV was out of order.（同位语从句）小王解决了电视机为什么出故障的问题。
以上例句中when,where和why作关系副词引导定语从句时，可以改为介词＋关系代词which来引导；而引导同位语从句的when,where和why就不能这样改。
综上所述，对与名词从句的学习可归纳出以下几点：
1.that引导名词性从句，其本身无词汇意义，仅起引导作用；除宾语从句外，that一般不能省略。
2.表示“是否”时，一般只用whether引导表语从句，主语从句和同位语从句。whether和if都可以用于引导宾语从句。
3.复合关系代词whoever,whomever,whosever,whichever,whatever引导名词性从句，有代替名词的作用：
①Whoever(=Anyone who)comes first may take it.
②You may do whatever(=anything that)you like.
③Return the book to whosever(=anyone whose)name is on it.
④You had better see the man for yourself and choose whichever(any one of them that)you like.
4.what在名词性从句中充当某一个成分（主语或表语或宾语），它具有双重含义：疑问意义，即什么，什么样的；②相当于“定语从句的先行词＋that…，可译为“所……的（东西或事情），如果去掉what，则从句本身不能成立，句意也不完整，试比较：
①They are thinking of what they should do.（宾语从句what=the thing(s)that）
②It worried her a bit that her hair was turning grey.她的头发正变白使她很焦急（that引导的从句作真正主语）。
5.从句的时态及主谓一致性。
名词从句的时态选择要与主句的时态基本保持一致。请看下面一道高考题。
Can you be sure——the goldring?
A.where Alice had put
B.where had Alice put
C.where Alice has put
D.where has Alice put
根据名词性从句的语序为陈述句语序的原则，选项B、D可排除，再据时态一致原则，可知答案为C。
从句作主语时，主句的谓语动词要用第三人称单数；从句作表语、宾语及同位语，主句的谓语动词的所用形式与它们无关；此外，在所有名词性从句中，其从句本身的谓语动词形式应与从句的主语保持一致，如：
How we can get there is unknown.
We know that he is an American.
附：名词性从句引导词一览表
