巧用还原法突破单选题

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高考英语试题解题方法之英语单选题解题10招

高考英语试题解题方法之英语单选题解题10招

高考英语试题解题方法之英语单选题解题10招高考英语的考试中选择题是最多的,面对选择题当然要比填空题会好选一些,不过如何在四个选项中选择到最佳的答案呢?除了与日常的知识积累有关系,还有其他的一些技巧吗?单项填空题在高考试题中是一种知识考查题,由于这一部分知识覆盖面广,加之每年高考都有若干个陷阱题和难题,使得考生对有些题目望而生畏。

本文分析了高考单项填空题的测试特点,具体阐述了这一题型的10种解题技巧,目的是帮助学生掌握这些解题方法,从而轻松答题。

第一招:还原法高考命题常以复杂的句型来增加考题的难度,有意给学生造成理解和判断上的困难。

面对这种题型,考生要能透过复杂的语言环境,结合语法结构,还原出“庐山真面目”。

这样题目就会变得简单,答案就会一目了然。

这种结构常为:1)将疑问句还原为陈述句;2)将强调句还原为陈述句;3)将感叹句还原为陈述句;4)将倒装句还原为正常语序;5)将被动语态还原为主动语态。

1. 将疑问句还原为陈述句【典型考题】例1: Is this school_______ you visited last month?A. oneB. the oneC. thatD. what【指点迷津】这是一个一般疑问句,如果不用还原法考生会误把this school分析成定语从句的先行词,反而掉进C项that这个陷进。

如果把句子还原成陈述句This school isyou visited last month,考生就可以看出这个定语从句缺少先行词the one和引导词that / which。

the one 特指this school, that / which作宾语可以省略。

因此答案是B项the one。

例2: What have we said _______ her so unhappy?A. makesB. to makeC. madeD. had made【指点迷津】答案为B。

这是一个特殊疑问句,如果把句子还原成We have said what _______her so unhappy,显然to make 作结果状语。

“还原法”——解答颖难单选题的一把金钥匙

“还原法”——解答颖难单选题的一把金钥匙

的结 构 , 这样 题 目就 会 变得 简单 , 案也会 答

目 了然 了。
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t e t c f r a we k a a h r k o u e s
tet c raw e sp nsm n. 因在使动词 m k h r k f ek a u i et u o h 又 ae等后
的宾语补足语用省 略 t动词不定式 , o 但在被动语态 中要 加上 省去 的动词不定式符 号 t, o故答案 为 A 。
二 、 问 旬 还 原 为 陈 述 旬 疑
A. e e wh r B\ . Cte o e . n h D. i h wh c
c u t h t1 w s d tr n d t e r n l h o n r t a a e emie o la n E gi . y s
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w i t e r ao e v i d 3 y as g ? se
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还原法解题的三种方法

还原法解题的三种方法

1. 回溯法:回溯法是一种暴力穷举法,它尝试所有可能的解决方案,从而找到最优解。

它通常用于搜索问题,其中搜索空间可以表示为树结构。

该方法逐步构建树结构,直
到找到解决方案为止。

2. 分支定界法:分支定界法是一种近似算法,它试图在有限的时间内找到最优解。


从搜索树的根结点开始,并且每次只考虑一个子结点。

它假设将子结点扩展到最优解,并且不会考虑其他结点。

3. 贪心算法:贪心算法是一种近似算法,它试图在每一步选择最优解,从而导致最终
的最优解。

它的思想是在每一步尝试最有利的选择,以期望在最终得到最优解。

单选题解题法(还原法)(网友来稿)

单选题解题法(还原法)(网友来稿)

单选题解题法(还原法)(网友来稿)高考一些单项选择题的测试点本来十分简单,但命题者有意把题干复杂化,改写为一个少见或陌生的结构。

对于这类题,应试者可以反其道而行之,把题干还原为自己熟悉的结构,这样,题目就会变得简单,答案就会一目了然,具体来说,可采用以下几种方法:一、将倒装句改成陈述句。

由于倒装句的使用,句子的结构变得陌生,对于这类题,可将题干还原成一个陈述句。

如;1. Whom would you rather have ___with you ?A. to goB. goC. goneD. going分析:本题题干改成陈述句,则应是:Would you rather have whom ___with you?这样我们一眼就可以看出答案为B。

测试的知识点是使役动词have的宾语补足语用动词原形表示将要2.Never ___time come back again.A. will loseB. will lostC. will losingD. will to lose分析;本提的答案选B。

如果将这个句子改为陈述句后,我们便可以很容易地看出其结构为:Losing time will never come back again.由于命题时将句子改写成倒装句,题目便具有很大的迷惑性。

二、将陈述句改为倒装句。

我们首次接触时是一个倒装句,而命题者恰恰是有意地使用陈述句来命题。

如:1. We had ____left home then it began to rain.A. no soonerB. hardlyC. almostD. nearly分析:No sooner...then是一个大家十分熟悉的句型。

在考察知识点时,命题者却使用了一个陈述句。

如果把题干改成:____ had left home then it began to rain.这道题的答案A也就变得十分清楚了.2. We had ___arrived at the train station when the train began to move.A. no soonerB. hardlyC. almostD. nearly分析:如果把本题改为倒装句,句子的结构就变得很熟悉了本题考察的是句型:hardly...when(一......就).答案应为B.三、去掉从句或插入语。

巧用还原法 快解单选题

巧用还原法 快解单选题

巧用还原法快解单选题
柳丽萍
【期刊名称】《中学生英语读写:高考版》
【年(卷),期】2004(000)009
【摘要】在英语的单项填空题中,有许多是针对考生解题的思维定势所设计的“陷阱题”。

出题人往往通过变化句子结构,把简单的句子改写成一个少见或陌生的结构,来干扰学生的思路,使学生误入“歧途”。

对于这类题考生可以反其道而行之,把
【总页数】3页(P36-38)
【作者】柳丽萍
【作者单位】湖南浏阳九中
【正文语种】中文
【中图分类】G633.41
【相关文献】
1.巧用关键词妙解单选题 [J], 刘新会;
2.运用还原法巧解单选题 [J], 骈晓;胡国梅
3.浅谈还原法在解单选题中的运用 [J], 邵玉静
4.“还原法”——解答颖难单选题的一把金钥匙 [J], 康瑞祥
5.十大技法快解英语单选题 [J], 董晓敏
因版权原因,仅展示原文概要,查看原文内容请购买。

三年级奥数学习讲义 第30讲 用还原法解题 练习及答案

三年级奥数学习讲义 第30讲 用还原法解题 练习及答案

三年级奥数学习讲义第30讲用还原法解题练习及答案----8b8db6c6-6ea6-11ec-a297-7cb59b590d7d
三年级奥数学习讲义第30讲用还原法解题练习及答案
第30课通过减少来解决问题
一、专题简析:
“一个数字加3,乘3,减3,最后除以3。

结果仍然是3。

这个数字是什么?”如果我们知道这样一个数的变化过程和最终结果,并找到了原始数,我们通常称之为“约化问题”。

为了解决恢复问题,我们通常使用反向方法。

简言之,我们会逆向思考。

要解决恢复问题,我们可以从结果出发,根据问题的含义,朝着其变化的相反方向一步一步地向后思考,直到问题得到解决。

同时,线段图表格可以帮助理解问题的含义。

2、精练
例1:一个减24加上15,再乘8得432,求这个数。

预期数学岛练习1
一、一个数加上3,乘3,再减去3,最后除以3,结果还是3。

这个数是几?
2.将一个数字乘以4乘以6减10,再乘以2得到88。

1
例2:对于一块布,第一次剪一半,第二次剪另一半。

还有8米。

这块布有多少米?
练习二
水果店卖西瓜。

其中一半是第一次出售,另一半是第二次出售。

此时,还有10个西瓜。

有多少原汁原味的西瓜?
2、某人乘船从甲地到乙地,行了全程的一半时开始睡觉,当他睡醒时发现船又行了睡前剩下的一半,这时离乙地还有40千米。

甲、乙两地相距多少千米?
二。

在定语从句中巧用还原法

在定语从句中巧用还原法定语从句是英语基础语法的一部分, 同时也是高中阶段语法教学中的重要部分. 但许多学生在定语从句的掌握和运用方面存在困难,做题时感觉云里雾里.采用“还原法”能帮助学生理清思路.“还原法”是指将因语法需要而改变的句子恢复其原来的模式,以检验所做的答案正确与否.“还原法”的运用1.将先行词还原到定语从句中,确定其在从句中所充当的成份,以选择正确的关系词.1).He has moved to the house ___he was born.A. whichB. thatC. whenD. where2). He has moved to the house____ is newly painted.A. whichB. /C. whenD. where3). I can think of many cases _____ students obviously knew a lot of English wordsand expressions but couldn’t write a good es say.A. whyB. whichC. asD. where4). He’s got himself into a dangerous situation____ he is likely to lose controlover the plane.A. whereB. whichC. whileD. why5). This is the reason ______ he asked us to carry out the plan.A. becauseB. whyC. whichD. when6). This is the reason ______ he gave us for carrying out the plan.A. becauseB. whyC. whichD. when2. 还原主句,理清主从句之间的关系,以免误入“陷阱”.1).Alac asked the policeman _____ he worked to contact him whenever there was an accident.A. with himB. whoC. with whomD. whom2).Is there a cinema around ____ I can see a film?A. thatB. whichC. whereD. whatIs this the garden around ___ there are many trees and flowers?3).The country life he was used to ____ greatly since the opening policy.A. changeB. has changedC. changingD. Having changed4). The theory he stuck _____ correct many years later.A. to provingB. to provedC. to proveD. proved5). I’ll do everything______ you.A. I can to helpB. I can helpC. what I can to helpD. that I can help6).Is this the watch you wish ________?A. to have it repairedB. to have repairC. to have repaired itD. to have repaired3. 把问句还原成陈述句,有助于正确理解句子.1).Who do you consider _____ your computer?A. to stealB. had stolenC. stealingD. to have stolen2).Who would you rather ____with you tomorrow, Tom or Smith?A. have to goB. have goC. have goneD. had go3).Is this park _____ you went to last Sunday?A. whichB. thatC. the oneD. where4).Is this the park ___you went to last Sunday?5).Is this the park ___you went last Sunday?EXERCISES1.Here is so heavy a stone _____no one can move.A. thatB. whichC. asD. as to2.Here is such a heavy stone ___no one can move it.A. thatB. whichC. asD. as to3. My experiment failed once again. However, he did what he could ___ me with .A. helpB. to helpC. helpingD. helped4. ---- I can’t find Mr Smith . Where did you meet him this morning?---- It was in the hotel _____ he stayed.A. thatB. whichC. the oneD. where5. George Orwell,____ was Eric Arthur, wrote many political novels and essays.A. the real nameB. what his real nameC. his real nameD. whose real name6. ____ is reported in the newspapers, talks between the two countries are makingprogress.A. ItB. AsC. ThatD. What7. ____ is often the case, we have worked out the production plan.A. WhichB. WhenC. WhatD. As8. The English play _____ my students acted at the New Year’s party was a greatsuccess.A. for whichB. at whichC. in whichD. on which9.The journey around the world took the old sailor nine months, ____ the sailingtime was 226 days.A. of whichB. during whichC. from whichD. for which10. What is it about a treeless, grimy, old city like St.Samothene _____ makespeople love it so much?A. thatB. itC. whereD. this11. There are altogether eleven books on the shelf , _____ five are mine.A. on whichB. in whichC. of whichD. from which12. A modern city has been set up in ____was a wasteland ten years ago.A. whatB. whichC. thatD. where13. _____is known to us all, Beijing is now preparing for the 2008 Summer Olympics.A. WhatB. ItC. WhichD. As14. _____is known to us all is that Beijing is now preparing for the 2008 SummerOlympics.A. WhatB. ItC. WhichD. As15. _____is known to us all that Beijing is now preparing for the 2008 SummerOlympics.A. WhatB. ItC. WhichD. As。

趣味数学之“还原法”解题(四年级适用)

钱。
自主探究3:贪心的商人
一个贪心的商人,整天都想发财。一天,他 在路上遇到了一位魔法师。魔法师说:“我这里 有一个神奇的盒子,只要把金币放到这盒子里后 数到十,金币就会变成原来的2倍。但是每次你 要付给我80个金币钱作为盒子使用费”。 商人听后,心想:发财的机会终于到了。于 是他与魔术师约定:每变一次,商人都付给魔术 师80个金币钱作为盒子使用费。
第二关:
1.篮子里有一些梨,小刚取走总数的一半 多1个,小明取走余下的一半多一个,小军取走了 小明取走后剩下的一半多一个,这时篮子里还 剩1个,问篮子里原来有梨多少个?
2.一筐桃子,大猴子吃了一半少2个,小 猴子吃掉剩下的桃子的一半多5个,然后两只 猴子又一起吃了10个桃子,最后还胜下11个。 问这筐桃子有多少个?
剩下的平均分三份,也把自己那一份藏起来 。
第三只猴子也是这样,扔了一个后平均分成三份,
藏起自己的那一份。最后剩下6个桃子。
小朋友们,你知道原来一共有多少个桃子吗?
真相还原:
第一步:先从“最后剩下6个桃子”,还原出第三个 猴子偷偷爬起来时看到的桃子数。
6÷2×3+1=10(个)
第二步:用同样的方法还原出第二个猴子偷偷爬起 来时看到的桃子数。
60+80=140元,得出商人第一次放进盒子的钱, 也就是商人原来自己身上的钱: 140÷2=70元.
自主探究4:小军的得分
一次英语考试后,明明问小军英语考试得多
少分。小军说:“用我得的分数减去6加上20,
再除以7,最后乘以4,得56.”小朋友,你知道小
军得多少分吗?
真相还原:
反过来从结果开始,乘法变除法,除法
第三关:阿凡提买菜
阿凡提去赶集,他用钱的一半买肉,再用 余下钱的一半买鱼,又用剩下钱买菜。别人问 他带多少钱,他说:“买菜的钱是1、2、3;3、 2、1;1、2、3、4、5、6、7的和;加7加8, 加8加7、加9加10加11。”你知道阿凡提一共 带了多少钱?买鱼用了多少钱?

识破陷阱好解题——巧用“还原法”解单项选择题

识破陷阱好解题——巧用“还原法”解单项选择题纵观近几年高考英语单项选择试题,题目涉及的知识面越来越广,难度也越来越大。

命题设计时使用的一些技巧或者说设置的一些陷阱,无形中增加了试题的难度。

这就需要学生们“拨开层层迷雾”,揭开单项选择题的“神秘面纱”,随之而来的将是柳暗花明的另一种境界。

下面举例说明几种巧用“还原法”解单项选择题的解题技巧,以帮助学生识破题目陷阱,正确解题,以提高解答单项选择题的得分率。

1. 将省略句还原成完整句例1—Who is making so much noise in the garden?— ___ the children.A. There areB. They areC. That isD. It is分析:本题考查的是强调句型。

此题的答语使用了省略的形式,增加了试题难度。

但将答语补充完整,还原为完整句:It is the children that are making so much noise in the garden.后,就不难看出此题是在考查强调句,正确答案显而易见应为选项D。

例2— What made Alice so upset?— ___ her new bike.A. As she lostB. LostC. LosingD. She lost分析:根据题意将题干的答语部分补充完整应为:___ her new bike made Alice so upset.可以看出“___ her new bike”是句子的主语,而在备选项中能够充当主语的只有选项C,即动名词短语充当主语。

[解题指导]学生们在解答此类题目时,可以先还原句子中被省略的成分,以使句子结构变得完整、清晰,从而选择出最佳答案。

2. 将疑问句还原成陈述句例3Was it in 1949 ___ our country was founded?A. thatB. whileC. in whichD. when分析:将题干还原成陈述句It was in 1949 ___ our country was founded.后,就不难看出此题考查的是强调句型,强调时间状语in 1949,故应选表强调结构“It was ___ that ___”中的that。

高考单选题答题技巧

高考单选题答题技巧1.排除法排除法是解选择类题型的最常见的方法,就是说,在审读题干时,首先排除在意义,语法要求上明显不合题目要求的选项,以便于我们集中精力,认真仔细地分析剩余的选项。

例:---Are the two answers correct?---No, ______ correct.A. no one isB. both are notC. neitherD. either is not解析:C 关键在“the two”, 故排除A,又因为回答是否定的,故排除B,D2.简化法命题者有意地在一个句子中间插入从句,插入语或附加的次要信息,造成主谓分离。

解题时,如果将题干中的多余部分去掉,题干就会变得简单,答案也就可以迅速找到。

例:A fast food restaurant is the place ______, just as the name suggests, eating is performed quickly.A. whichB. whereC. thereD. what解析:B可先划去just as the name suggests, 这样可清楚地看出空白线后是一个定语从句,应当用where(=in / at which) 引导该定语从句修饰先行词place.3.找提示词法(1)提示词对有些题目来说,若能找准关键的提示词(如but, and, otherwise 等),题目就迎刃而解了。

例:Don’t be discouraged. ______ things as they are and you will enjoy day of your life.A. TakingB. To takeC. TakeD. Taken解析:C 关键词”and”,就可知道前句为祈使句,有一个and加祈使句的用法(2)提示句例:Shirley ______ a book about China last year but I don’t know whether she has finished it.A. has writtenB. wroteC. had writtenD. was writing解析:D 从后面的信息“but I don’t know whether she has finished it”可得知她当时正在写,有无完成还不知道。

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_____ you said we were to stay in your letter? A. that B. where C. the one D. in which 4. Please tell me the way you thought of ___ the garden. A.take care of B. to take care of C. taking care of D. how to take care of
5. The “Two Cities” referred ___ London and Paris. A. is to B. to be C. to are D. to going to be 6. Is there a shop around ___ we can buy some toilet articles? A. that B. which C. where D. what 7. --Who are making so much noise --Who garden? in the garden? ---_______ ---_______ the children. A. It is B. They are C. That is D. There are
---We 14. ---We haven't heard from Jane time. for a long time. ---What her? ---What do you suppose __ to her? A.was A.was happening B. to happen C. has happened D. have happened 15. He made another wonderful discovery, discovery,____ of great science. importance to science. A.which A.which I think is B. which I think it is C. which I think it D. I think which is
1~5 DBCBC 6~10 CAACB 11~15 ACDCA
16. The little boy was caught ____ in the shop. A. to steal B. stealing C. steal D. stole ---How 17. ---How long has this business? bookshop been in business? --- ______ 1982. A. After B. In C. Since D. From 18. I would mend your radio, but I don’t know _________. A. how B. to C. how to D. to how
1. Mr. Wang made up his mind to devote all he could ____ his oral English before going abroad. A.improve B. to improve C. improving D. to improving 2. You can never imagine what great difficulty I have _____ your house. A. found B. finding C. to find D. for finding
---Hey Hey, 8. ---Hey,look where you are going! going! ---Oh Oh, ---Oh,I’m terrible sorry____. A. I’m not noticing B. I wasn’t noticing C. I haven’t noticed D. I don’t notice 9. He would have succeeded ____he followed my advice. A. When B. If C. Had D. Has
9.还原强调句为陈述句 9.还原强调句为陈述句
例9: It was _____ the old clock that the old man spent the whole morning at home. A. repair B. repairing C. to repair D. in repair 练一练---Who was it that went with our teacher? ---___ Amy and Susan. A. It is B. It was C. They were D. They are
3.将感叹句还原为陈述句 3.将感叹句还原为陈述句
例3:How excited we were ___ such an interesting film. A. see B. seeing C. to see D. seen 练一练: You can never imagine what great difficulty I have _____ your house. A. found B. finding C. to find D. for finding
4. 整句还原法
例4: “What were you trying to prove to the police?” “_____ I was last night.” A. That B. When C. Where D. What
练一练 “What made her so happy”? “____ her son passed the college entrance examinations.” A. That B. 不填 C. Since D. For
7.去掉插入语还原成简单的句子 7.去掉插入语还原成简单的句子
例7:John plays football ___, if than, not better than,David. B. A. as well B.as well as D. C. so well D.so well as 练一练Who do you think ___us a talk this afternoon?. A. giving B. to give C. gave D. will give
1. 将疑问句还原为陈述句
例1:Is this book _____ you bought last month? A. one B. the one C. that D. what 练一练: 练一练:Who would you rather ____ with you? A. go B. to go C. going D. gone
8.倒装句还原为陈述句 8.倒装句还原为陈述句
例8:On the grass __two sheep. A. lies B. lie C. laid D. lying 练一练At the meeting place of the
Yangtze River and the Jialing River______, one of the ten largest cities in China. (10重庆) A. lies Chongqing B. Chongqing lies C. does lie Chongqing D. does Chongqing lie
10.还原承上句省略的时间状语 10.还原承上句省略的时间状语
Tom, 例10: ---Tom,why did you 10: ---Tom make no reply to me when I called your name in the street just now? ---Sorry, ---Sorry, Jim. I ___ to my wife on the phone. B. A.was talking B.talked D. C.am talking D.had talked
novels, 10. He wrote five novels,two of ____translated into English. A. it B. them C. which D. that ---Tom Tom, 11. ---Tom,why did you make no reply to me when I called your name in the street just now? ---Sorry Sorry, ---Sorry,Jim. I ___to my wife on the phone. B. A. was talking B.talked D. C.am talking D.had talked
5.补充省略成分确定正确选择 5.补充省略成分确定正确选择
例5:We would have to put off the visit to next month _____ it rain tomorrow . A. were B. should C. would D. will 练一练If ___ the same treatment again,he is sure to get well. A. giving B. give C. given D. being given
2.将被动语态还原为主动语态 2.将被动语态还原为主动语态
例2:Time should be made good use of _____ our lessons well. A. improving B. improved C. to improve D. being improving 练一练: 练一练:Much of his time was devoted to ____ the children in that area. A.help A.help B. helped C. helping D. being helped
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