名词性从句相当于名词,可用作主句的主语、表语、宾语和同位语。因此,名词性从句分为主语从句、表语从句、宾语从句和同位从句。引导名词性从句的连接词有:连接代词:who, whose, whom, what, which,有词义,在从句中担任成分,如主语、表语、宾语、或定语等;连接副词:when, where, why, how,有词义,在从句中担任成分,作状语;连接词:that, whether, if, as if,if (whether), as if虽有词义,但在从句中不担任成分;that 无词义,在从句中不担任成分,有时可省略。 csd~)a nb
今后对名词性从句的考查仍将集中在关联词的选用上,特别石堆what引导的名词性从句的考查。名词性从句与其他从句的混合考查将在今后高考中占据一席之地。易混句型的辨析,比如it作形式主语,主语从句后置的句型与强调句型的辨析将仍作为高考考查的重点。 TCL XO0
【知识点归纳】 k
E},>+W+
名词性从句的用法 7@NV|Idtd
在句子中起名词作用的句子叫名词从句 (Noun Clauses)。 名词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。 3Jh!YzI8
一、引导名词性从句的连接词 8-&c%h
1
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”)。 v 1VH&~e
以上在从句中均不充当任何成分 t8ZzBD!dP
连接代词:what, whatever, who, whoever, whom, whose, which. Whichever, whomever _C
54l
连接副词:when, where, how, why Wi+}qO
不可省略的连词: ]k#iA9I
1. 介词后的连词 'D:R]@eK]
2. 引导主语从句和同位语从句的连词不可省略。 UGD B4S
That she was chosen made us very happy. `Iqh\oY8-
We heard the news that our team had won. + usB$=kJ
比较: ;u*I#)7
Whether与if 均为"是否"的意思。 但在下列情况下,whether 不能被if 取代: <f9a%`d
1. Whether引导主语从句并在句首; )qua0'y]@
2. 引导表语从句 wA2^I70-
3. Whether从句作介词宾语; CxD=8X9m
4. 从句后有"or not" {`ByZB
Whether he will come is not clear. ,v#O{ma
大部分连接词引导的主语从句都可以置于句末,用 it充当形式主语。 z)ndj
1,#)
It is not important who will go. _A~>?gJ;,
It is still unknown which team will win the match. Tvl"KVGm
二、具体分类 :!/ (N
1.主语从句 ] B?NDxU
作句子主语的从句叫主语从句。主语从句通常由从属连词that,whether,if和连接代词what,who,which,whatever,whoever以及连接副词how,when,where,why等词引导。that在句中无词义,只起连接作用;连接代词和连接副词在句中既保留自己的疑问含义、又起连接作用,在从句中充当从句的成分。例如: {_R{gpj'
What he wants to tell us is not clear. 他要跟我们说什么,还不清楚。 &)izh) FA
Who will win the match is still unknown. 谁能赢得这场比赛还不得而知。 va2FgW`Bd+
It is known to us how he became a writer. 我们都知道他是如何成为一名作家的。 i<{:J -U|
Where the English evening will be held has not yet been announced. 英语晚会将在哪里举行,还没有宣布。
:(YFIW`59
【典例1】It is immediately clear ____ the financial crisis will soon be over. g=$nNQ
\6=
A. since B. what C. when D. whether 8[H bg
【答案】D c"diNbm[
【解析】考查主语从句的用法。该句的意思时:经济危机是否会很快结束是很明显的事情。“是否”用whether表示,不能选when是因为从句中由soon这一实践状语。 3Mq%3jX
【典例2】_____ was most important to her, she told me, was her family. ?
=I']$MH
A. It B. This C. What D. As AO,^v+$
【答案】C aUi^7;R&<
【解析】she told me是插入语,可删除。what引导主语从句,在从句中充当主语。 88VI
_
<
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: (QS 0
(1)It + be + 名词 + that从句 >avkiT2
(2)It + be + 形容词 + that从句 \c1>15
(3)It + be + 动词的过去分词 + that从句 p_i',5H(
(4)It + 不及物动词 + that 从句 [QIQpBL
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: uNca@xl'
It is necessary (important, natural, strange, etc.) that … ]:}7-;$V
It is a pity (a shame, no wonder, etc.) that… sB!6"D5
It is suggested (requested, proposed, desired, etc.) that… j_.tg7X
【典例】It is obvious to the students ______ they should get well prepared for their future. 4
|UtE<<b
A. as B. which C. whether D. that -EE
}HUP)
【答案】D !{CaW4
【解析】考查名词性从句。本空格处应是一个主语从句的引导词,因该主语从句不缺成分,且句意完整,故应用不作任何成分的连词that。 p!EG:B
4
2.宾语从句 :o:Z
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。 :`c@&WF8
(1) 由连接词that引导的宾语从句 ,ZVhL* "
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: o7^0Lo5Z?
He has told me that he will go to Shanghai tomorrow. 他已经告诉我他明天要去上海。 `O!yt
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。 ,BR W=
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: [#fz[U
I insist that she (should) do her work alone. 我坚持要她自己工作。 $wbIe"|
The commander ordered that troops (should) set off at once. 司令员命令部队马上出发。 ?@<Tzk]a.
(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: .*Z#;3
I want to know what he has told you. 我想知道他告诉了你什么。 qC3PKlhv6
She always thinks of how she can work well. 她总是在想怎样能把工作做好。 2cwJ);Eg2
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。 LYiIJAZ.
【典例1】The companies are working together to create _______ they hope will be the best means of transport in the 21st century. "N)InPR-
A. which B. that C. what D. who 3S1{r
)[j
【答案】C NN5G
'|i
【解析】create后为宾语从句,从句中they hope是插入语,可删除。因为从句中缺少主语,所以用what引导该从句。 T-]UAN"O
【典例2】Could I speak to is in charge of International Sales please? ce*?crOV
A. who B. what C. whoever D. whatever P<;Puww/
【答案】C ,!X:wY}dW
【解析】 考查名词性从句。题干中介词to后面为宾语从句,从句中缺少主语,因此填whoever。 5=Y(.}6
(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: "'XYW\bI
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: *?VB/yO=0
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。 SwaMpNXL
The question is whether she should have a low opinion of the test? .EvP%A
m
Everything depends on whether we have enough money. 一切要看我们是否有足够的钱。 BqM[{Kv
I wonder whether he will come or not. 我想知道他来还是不来。 1~j,A[&|<
Can you tell me whether to go or to stay? 你能否告诉我是去还是留? J(A+mYr{:
(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 5kA D vi.
不同时态。例如: )@] W=
he studies English every day. (从句用一般现在时) )6eFYt%c
he studied English last term. (从句用一般过去时) ?j)#\s2
I know (that) he will study English next year. (从句用一般将来时) T5}5uk9
he has studied English since 1998. (从句用现在完成时) ~#)9Kl7<X
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: 02)Ybp6y
The teacher told us that Tom had left us for America. nFe
(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: 8#9OSupp
We don’t think you are here. 我们认为你不在这。 NRk^Z)
I don’t believe he will do so. 我相信他不会这样做。 P7REE_<1
3.表语从句 9;rZ )QD
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: L X #.
The fact is that we have lost the game. 事实是我们已经输了这场比赛。 [4@@b"H
That’s just what I want. 这正是我想要的。 JeAyT48!M
This is where our problem lies. 这就是我们的问题所在。 85Kf>z::c
That is why he didn’t come to the meeting. 那就是他为什么不到会的原因。 z6
h/C{
It looks as if it is going to rain. 看上去天要下雨了。 tf1Y5P$
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: ?%/*F<UVQ
The reason why he was late was that he missed the train by one minute this morning . '*t<g@2$
【点拨】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。 Q8h=2YL
【典例1】The little girl who got lost decided to remain ________she was and wait tor her mother. +eop4 |Z
A. where B. what C. how D. who 1{
ehnH
【答案】A 6)FM83zk)K
【解析】remain是系动词,后加表语从句,由句意可知,从句缺地点状语,所以选A。 Fl"LK:)
【典例2】The last time we had grat fun was _______ we were visiting the Water Park. faZc18M^1
A. where B. how C. when D. why GkKoc v
【答案】C %;J$ h^
【解析】was后为表语从句,此处when与the last time相呼应,根据句意可排除其他选项。 1 -R4A7+3
4. 同位语从句 h(^[WSa
同位语从句说明其前面的名词的具体内容。同位语从句通常由that引导,可用于同位语从句的名词有advice,demand,doubt,fact,hope,idea,information,message,news,order,problem,promise,question,request,suggestion,truth,wish,word等。例如: #jg3Ku;Y
The news that we won the game is exciting. 我们赢得这场比赛的消息令人激动。 JqEo~]E]
I have no idea when he will come back home. 我不知道他什么时候回来。 SK_N|X].
The thought came to him that Mary had probably fallen ill. 他想到可能玛丽生病了。 -&QpQ7q1
【典例】We should consider the students’ request ________ the school library provide more books on popular science. 6*I=%
H|
A. that B. when C. which D. where 5o0H7k]
【答案】A ~Q=^YZgn8
【解析】考查名词性从句。根据题意知,空格处是同位语从句的引导词,修饰中心名词request,且在句子中不充当成分,故用that。这句话的意思是我们应该考虑学生的这个要求,即学校图书馆应该多提供一些大众科学方面的书籍。 ntZH
O}'
三、对比与用法 g=Nde2d?
1.同位语从句和定语从句的区别: c{jTCkzq
that作为关系代词,可以引导定语从句,充当句子成分,在从句中作宾语时可以省略; that引导同位语从句时,起连词的作用,没有实际意义,不充当句子成分,一般不能省略。 0 Gq<APtr
试比较下面两个例句: W@~a#~1O
I had no idea that you were here.(that引导同位语从句,不能省略) #O7phjzgD
Have you got the idea(that)this book gives you of life in ancient Greece?(that引导定语从句,作宾语,可以省略) VZ2CWE)t
2.that-从句作主语通常用it作先行词,而将that-从句置于句末。 '/Xm%S
用it作形式主语的that-从句有以下四种不同的搭配关系: Nm3CeU
a. It + be +形容词+ that-从句 Nxm '*
-A
It is necessary that… 有必要…… >E>'9@Uh
It is important that… 重要的是…… BqOMg$<\[
It is obvious that… 很明显…… a3:1`c/~\
b. It + be + -ed 分词+ that-从句 >
}86#^F
It is believed that… 人们相信…… T lB+
tV>
It is known to all that… 从所周知…… "}<baz
It has been decided that… 已决定…… N$cAX^~
c. It + be +名词+ that-从句 PxJvE*6^H
It is common knowledge that… ……是常识 :n oZ
p:a
It is a surprise that… 令人惊奇的是…… 7#9fcfL
It is a fact that… 事实是…… 0Rh*SoYrC
d. It +不及物动词+ that-分句 u"kB`||(
It appears that… 似乎…… <{.pYrn
It happens that… 碰巧…… EL9JM}%0v
It occurred to me that… 我突然想起…… qvRs1yr?q
It is quite clear that the whole project is doomed to failure. N\x<'P4q
很清楚,整个计划注定要失败。 prVqV-S6TY
It's a pity that you should have to leave. w#
;y
你非走不可真是件憾事。 RIF*9= ,S
3.否定转移 D*)"?LG
(1) 将think, believe, suppose, expect, fancy, imagine等动词后面宾语从句的否定词转移到主句中,即主句的谓语动词用否定式,而从句的谓语动词用肯定式。 ZZW%6 -B
I don't think I know you. 我想我并不认识你。 iD:TKB_r
I don' t believe he will come. 我相信他不回来。 5K$d4KT
注意:若谓语动词为hope,宾语从句中的否定词不能转移。 kJ B u7
I hope you weren't ill. 我想你没有生病吧。 e]smnf
(2)将seem, appear 等后的从句的否定转移到前面。 !A"-9OS2
It doesn't seem that they know where to go. }yM!o`
90
看来他们不知道往哪去。 Qh4Z{c@
It doesn't appear that we'll have a sunny day tomorrow. _Ns_$_
看来我们明天不会碰上好天气。 Oa7jLz'i
【备考策略】 :"Kr-Hm`
考生对于名词性从句的复习和应试关键要把握每个引导词的意义,因为在对于名词性从句的考查中,引导词在句子中都起作用,有意义,因此在分析句子结构,对比辨别名词性从句、状语从句、强调句式后,最后还是要选择引导词;另外还要注意以下几点: vi0nJ -Xg
1.what 引导词的考查,尤其位于介词后引导的宾语从句以及引导名词性从句时的双重作用。 }zHG]k,j
2.Whether和if 的区别,尤其注意他们的不同之处。 ?,*KA Gg%
3.名词性从句和其它从句的兼容结构测试。 rh6m
4.句子语序和时态。
W/<