俗话说：麻雀虽小，五脏俱全。单项填空题虽然细小，却是最能反映学生英语能力的一种题型，更何况如今的单项填空题已完全实现了从过去单纯考查学生语法知识到考查学生语言运用能力的转变，换言之，如今的单项填空题就是微型的完形填空与语篇理解，同样需要学生前瞻后顾，同样需要学生整合、处理、运用语言信息的能力。这也是学生们对于单项填空题感到畏惧的原因。当然，单项填空题绝非不可攻破的堡垒，只要我们掌握还原法这一武器，我们完全可以把单项填空题这个强敌挑于马下，捉拿归案。
细细归纳，我们就会发现还原法又有不同的适用情况，下面我们分门别类作具体的讲述：
情况一、还复合句以简单句
[例证题]
The most favorite room is the tidy study with a fireplace,______we can watch TV and enjoy the nice scenery outside.
A． where B． when
C． that D． which
[分析]
此句实际上是两句简单句的合成，第一句：The most favorite room is the tidy study with a fireplace. 第二句：In the tidy study we can watch TV and enjoy the nice scenery outside. 根据第二句中tidy study作地点状语，我们可以看出应该用关系副词where, 相当于in which，答案是A。
[高考题]
After the war, a new school building was put up______there had once been a theatre.
A. that B. where C. which D. when
[分析]
此句实际上也是两句简单句的合成，第一句：After the war, a new school building was put up. 第二句：In the place there had once been a theatre. 根据第二句中缺少地点状语，我们可以看出应该用连词where, 相当于in the place where，答案是B。
[前瞻题]
The British are not so familiar with different cultures and other ways of doing things, ______is often the case in other countries.
A． as B． that C． so D． it
[答案及简析]
答案是A。此题相当于下面两句：The British are not so familiar with different cultures and other ways of doing things. It is often the case in other countries. 注意as也可以充当定语从句的关系代词，指代前面提到的整个句子。
情况二、还疑问句以肯定句
[例证题]
Why is ________ you are so late for school?
A． it that B. that it C． it D． that
[分析]
此句是特殊疑问句，肯定句的答语应该是这样的：
It is for this reason that I am so late for school.
如果对for this reason提问就得出以上疑问句： Why is it that you are so late for school?
显而易见，答案是A。
[高考题]
The mother didn't know______to blame for the broken glass as it happened while she was out.
A. who B. when C. how D. what
[分析]
此句是特殊疑问句，变成肯定句即：Somebody is to blame for the broken glass...所以对主语提问很简单地得出Who is to blame的句型。不过此题之所以入选高考题还因为它有中英文文化差异的问题，一般在汉语中我们说：他被责怪。然而在英语中我们必须用主动语态。
[前瞻题]
Is______three hours______the boy ______family is poor to come to school on foot?
A. it; that; whose B. it; when; that
C. it for; that it takes; who D. it; that it takes; whose
[答案及简析]
答案是D。此句的肯定形式是强调结构：It is three hours that it takes the boy whose family is poor to come to school on foot.
情况三、还省略句以完整句
[例证题]
—Are there any English story books for us students
in the library?
—There are only a few, ______.
A. if any B. if some
C. if there D. if has
[分析]
答案是A。此句是 There are only a few, if there are any.的省略形式。此外值得一提的是在条件状语从句中我们也必须用any来代替some。
[高考题]
—Susan, go and join your sister cleaning the yard.
—Why______? John is sitting there doing nothing.
A. him B. he C. I D. me
[分析]
答案是D。此题是Why do you ask me to do so?的省略形式。
[前瞻题]
I'm looking forward as much to his return as he himself to______me.
A. have seen B. seeing
C. see D. be seen
[答案及简析]
答案是B。此句完整的句子是：I'm looking forward as much to his return as he himself is looking forward to seeing me. 注意：这里的to 是介词，千万不能望文生义而选择C。
情况四、还倒装句以正常句
[例证题]
Not until the work was______did he go to bed last night.
A. he finished B. finished
C. he had finished D. finishing
[分析]
答案是B。此句由于否定词放在句首，所以倒装。 正常的句子是：He didn't go to bed until the work was finished last night.
[高考题]
The old couple have been married for 40 years and never once______with each other.
A. they had quarreled
B. they have quarreled
C. have they quarreled
D. had they quarreled
[分析]
答案是C。此句就是因为否定词never放在句首，所以应该倒装，还有一个知识点是必须用现在完成时。
[前瞻题]
Little______what you said. Would you please explain it?
A. did I understand
B. I understood
C. I did understand
D. have I understood
[答案及简析]
答案是A。表示否定意义的副词放在句子最前面时应该倒装。
情况五、 还被动句以主动句
[例证题]
While shopping, people sometimes can't help______into buying something they don't really need.
A. persuade B. persuading
C. being persuaded D. be persuaded
[分析]
答案是C。people 是被说服做某事的，所以这里必须用被动语态。改成主动语态时的形式是：(The shop assistants) persuade people into buying something they don't really need.
[高考题]
A cook will be immediately fired if he is found______in the kitchen.
A. smoke B. smoking
C. to smoke D. smoked
[分析]
答案是B。此句是被动语态，如果改成主动形式便是：. . . find him smoking in the kitchen.
[前瞻题]
The manager promised to keep me______of how our business was going on.
A. to be informed B. on informing
C. informed D. informing
[答案及简析]
答案是C。inform sb.→sb. be informed。
情况六、还强调句以一般句
[例证题]
It is the village______he was born______I visited yesterday.
A. where; where B. that; that
C. that; where D. where; that
[分析]
答案是D。此题可还原如下：Yesterday I visited the village where he was born. 第一个空是定语从句，第二个空才是强调结构。
[高考题]
It was only when I reread his poems recently______I began to appreciate their beauty.
A. until B. that C. then D. so
[分析]
答案是B。此句是典型的强调结构。
[前瞻题]
Why was______you were absent from the meeting?
A. it that B. that it C. it D. that
[答案及简析]
答案是A。此句是强调结构的特殊疑问句形式，实际是: It was for this reason that you were absent from the meeting.
情况七、还虚拟句以真实句
[例证题]
If you had made good preparations before, you______about the coming examination.
A. would not be worried
B. would have worried
C. could not be worried
D. could not have been worried
[分析]
答案是D。此句是对过去情况的虚拟，所以主句必须用would/could/should/might have done...，be worried about 属于固定搭配。
[高考题]
—I stayed at a hotel while in
—Oh, did you? You______with Barbara.
A. could have stayed
B. could stay
C. would stay
D. must have stayed
[分析]
答案是A。该题也是对过去情况的虚拟。
[前瞻题]
I would love______to the cinema last night, but I had to look after my sick sister at home.
A. to go B. to have gone
C. going D. having gone
[答案及简析]
答案是B。would love to have done... 是对过去情况的虚拟，表示“本来想……”。
总之，掌握了还原法，你就能够化难为易，把复杂的句式简单化，从而能够游刃有余地扫除单项填空题这一英语学习中的拦路虎，高高兴兴学英语，轻轻松松得高分。
