很多同学分不清名词性从句和定语从句,实际上,区分它们很简单:定语从句在整个句子中的功能相当于形容词(词组),而名词性从句的功能则相当于名词(词组)。按照名词性从句的句法功能,可将其分为主语从句、表语从句、宾语从句和同位语从句。名词性从句是中学阶段的一个重要语法项目,在历年的高考英语中几乎都有所考查,并且每年的命题各有变化。笔者分析了历届高考试题中名词性从句的九大考点,本期先介绍其中的五个。
语序
名词性从句的语序应用陈述语序(即正常语序),且引导词要放在从句的最前面。
【真题再现】
① As soon as he comes back, I'll tell him when ______ and see him. (2005年北京卷)
A. you will come B. will you come
C. you come D. do you come
② When changing lanes, a driver should use his turning signal to let other drivers know ______. (2010年上海卷)
A. he is entering which lane
B. which lane he is entering
C. is he entering which lane
D. which lane is he entering
【解析】① A。这里when引导的从句作谓语动词tell的宾语,是宾语从句,应用陈述语序,由语境可知,从句的谓语动词应用将来时,故选A。② B。Which引导的宾语从句作谓语动词know的宾语,句子用陈述语序,故选B。
引导词
名词性从句的引导词很多,大部分都可以根据句意判断出所需的引导词,但要注意以下几组引导词的区别。
1. What与that的区别:what作连接代词并表示“所……的(东西)”之意,相当于“the +名词+ that /which”或“all that”,可指代不确定的事物,在从句中作主语、宾语或表语;而that在名词性从句中只起引导作用,不表达任何意思。
【真题再现】
① Before the sales start, I make a list of ______ my kids will need for the coming season. (2010年山东卷)
A. whyB. whatC. howD. which
② Part of the reason Charles Dickens loved his own novel, David Copperfield, was ______ it was rather closely modeled on his own life. (2010年北京卷)
A. whatB. thatC. whyD. whether
【解析】① B。题干的意思应为:“在大甩卖开始前,我把孩子们在下个季节里要用到的东西列了一个清单。”分析句子结构可知,整个从句是介词of的宾语,因此空格处在句中引导宾语从句,且在从句中充当need的宾语,故排除表方式的how和表原因的why;而which在引导名词性从句时多表示疑问“哪一个”,并且有一个明确的选择范围,故排除D;what相当于the things which,故选B。② B。题干的意思应为:“狄更斯喜欢他自己的小说《大卫·科波菲尔》的部分原因是小说创作非常贴近他本人的真实生活。”空格处所引导的表语从句中不缺少任何意义和成分,因此用that来引导。
2. Whether与if的区别:两者都表示“是否”,都可引导宾语从句,但下列情况只能用whether:①引导主语从句、表语从句、同位语从句时;②位于句首时;③后紧跟or not时;④作某些及物动词(如discuss、decide、argue等词)的宾语时;⑤与不定式连用时;⑥作介词的宾语时。因此,若if与whether同时出现在选项中,当表示“是否”之意时,一般情况下舍if选whether。
【真题再现】
We haven't settled the question of ______ it is necessary for him to study abroad. (2006年江苏卷)
A. ifB. whereC. whetherD. that
【解析】C。题干的意思应为:“我们还没有解决他是否有必要出国留学这个问题。”此处是宾语从句,表示“是否”,且作介词of的宾语,故用whether。
3. Wh-与wh-ever的区别:wh-ever引导宾语从句时,含有“无论……”之意,其引导宾语从句时无疑问意义,而wh-多有疑问之意。
【真题再现】
① To improve the quality of our products, we asked for suggestions ______ had used the products. (2010年重庆卷)
A. whoever B. who
C. whichever D. which
② ______ makes this shop different is that it offers more personal services. (2006年辽宁卷)
A. WhatB. WhoC. WhateverD. Whoever
【解析】① A。Whoever相当于anyone who,其引导的从句作ask的宾语,这里将宾语从句后置来保持句子平衡,可还原为:... we asked whoever had used the products for suggestions。题干的意思为:“为了提高产品质量,我们向那些使用过该产品的人们征求意见。”② A。What引导主语从句,并在从句中充当主语,相当于the thing that。题干的意思为:“这家商店的与众不同之处在于它提供更多的个性化服务。”
4. No matter + wh-与wh-ever的区别:no matter + wh-只能引导状语从句;而wh-ever既可引导状语从句,也可引导名词性从句。
【真题再现】
① The how to book can be of help to _______ wants to do the job. (2009年陕西卷)
A. who B. whomever
C. no matter who D. whoever
② ______ team wins on Saturday will go through to the national championships. (2006年山东卷)
A. No matter what B. No matter which
C. Whatever D. Whichever
【解析】① D。此处从作介词to的宾语可知,后面的从句是名词性从句,引导词作从句的主语,意思是“无论是谁”。由于no matter who不能引导名词性从句,而whomever只能作宾语,故选whoever。② D。空格处引导主语从句______ team wins on Saturday,并在从句中作team的定语,根据句意可知,应用whichever表示“无论哪一个”。
时态
名词性从句的时态多在宾语从句中考查,有以下几种情况:①当主句中的谓语动词是现在或将来时态时,从句的谓语不受主句谓语时态的影响,可根据句子的实际情况使用不同的时态;②当主句中的谓语动词是过去时态时,从句的时态也应是表示过去的时态;③当从句表示客观事实或真理时,其时态不受主句谓语时态的影响,而用一般现在时。
【真题再现】
① I was out of town at the time, so I don't know exactly how it ______. (2009年山东卷)
A. was happening B. happened
C. happens D. has happened
② She stared at the painting, wondering where she ______ it. (2009年重庆卷)
A. saw B. has seen
C. sees D. had seen
【解析】① B。本题考查具体语境中的时态,后一句隐藏的时间状语是at the time (在那时),故从句用一般过去时,不应该受到主句“I don't know exactly”中现在时态的影响。② D。本题也是考查具体语境中的时态,因wondering是stared的伴随状语,表示过去的动作,故从句中必定是过去时态,排除B、C选项;又因see的动作发生在stare之前,因此用过去完成时。
It作形式主语或形式宾语
为了保持句子平衡,常用it作形式主语或形式宾语,把真正的主语从句或宾语从句置于句末。
1. It作形式主语的常见结构:
(1) It + be +形容词+ that从句。例如:It is necessary that ... (有必要……);It is important that ... (重要的是……);It is obvious that ... (很明显……)等。
(2) It + be + 过去分词+ that从句。例如:It is believed that ... (人们相信……);It is quoted that ... (有消息说……);It has been decided that ... (已决定……)等。
(3) It + be +名词+ that从句。例如:It is common knowledge that ... (……是常识);It is a surprise that ... (令人惊奇的是……);It is a fact that ... (事实是……)等。
(4) It +不及物动词+ that从句。例如:It appears that ... (似乎……); It happens that ... (碰巧……);It occurred to me that ... (我突然想起……)等。
【真题再现】
① ______ is our belief that improvements in health care will lead to a stronger, more prosperous economy. (2006年浙江卷)
A. AsB. ThatC. ThisD. It
② The doctor thought ______ would be good for you to have a holiday. (2010年全国卷Ⅱ)
A. thisB. thatC. oneD. it
【解析】① D。考查it作形式主语,后面的that从句作真正的主语。② D。It在宾语从句中充当形式主语,真正的主语是to have a holiday。
2. It作形式宾语的常见结构:
(1)宾语从句+宾语补足语。这种结构为了保持句子平衡,常用it作形式宾语,把真正的宾语从句置于句末,常见的用it作形式宾语的谓语动词有believe、find、make、guess、suppose等,具体形式为believe / find / make / guess / suppose it +宾语补足语(一般为形容词)。
(2)某些及物动词或短语不能直接加宾语从句,此时用it作形式宾语,然后再接宾语从句,此种用法常见于like、dislike、hate、appreciate等谓语动词后。
【真题再现】
① He didn't make ______ clear when and where the meeting would be held. (2007年天津卷)
A. thisB. thatC. itD. these
② I'd appreciate ______ if you would like to teach me how to use the computer. (2006年山东卷)
A. thatB. itC. thisD. you
【解析】① C。此题考查的是谓语动词后加宾语的复合结构,clear是宾补,when and where the meeting would be held是真正的宾语,并置于宾补之后,故用it作形式宾语。② B。题干中if you would like to teach me how to use the computer是宾语从句,作appreciate的宾语,这种情况常用it作形式宾语。
否定转移
在宾语从句中,主句的谓语动词(词组)是think、believe、suppose、imagine、consider、expect、guess、be sure等,且主句的主语是第一人称并为一般现在时,对宾语从句的否定一般转移到主句上,表示说话者提出一种委婉的看法或主张,其反义疑问句一般与宾语从句的主语保持一致。
【真题再现】
I don't suppose anyone will volunteer, ________? (2001年上海卷)
A. do I B. don't I
C. will they D. won't they
【解析】C。由主句的谓语动词是suppose,主句的主语是第一人称并为一般现在时可知,反义疑问句应对宾语从句提问,再加上don't实际上是对宾语从句的否定,故反问句应用肯定形式,即will they。
作者简介:
王正勋,高中英语教师,执教于福建省泉州市泉港区泉港二中,国家基础教育实验中心外语教育研究中心研究员。