托福阅读推理题中那些“逆向推理”
新托福阅读推理题深度解析
新托福阅读推理题深度解析推理题的标志是在题干中出现infer/imply/suggest/indicate/most likely 这样的词汇，它和细节题属于同源题目，都需要定位并且根据文中信息来选择答案。
与细节题不同的是，推理题在找到原文中定位点之后考察的是学生对于文中信息的总结概括，或者反向推理的能力。
下面小编给大家带来新托福阅读推理题。
新托福阅读推理题深度解析推理题的两大分类：有共性的推理题和无共性的推理题。
这里所谓的有共性推理题就是说题干中有和原文内容相同的关键词(也叫线索)。
根据关键词回原文定位，然后进行推理。
一般来说，大多数的推理题都属于这类题目。
对于无共性的推理题，也就是题干中无线索，一般使用排除法，即根据各个选项的关键词回原文定位，通过排除法得出正确答案。
返回原文找信息点，采用排除法是解决这两类题型解决的共同策略。
推理题大概有三个解题思路：一般对比推理、时间对比推理、集合概念推理。
一般对比推理：根据两个事情的对比特征，问其中一个事物的特征，只要将与之形成对比的另外一个事情的特征否定掉就可以。
时间对比推理：在这种推理中，一般有两个形成对比的时间段，它们所具有的特征一般相反。
当题干问一个时间段的特征时，只要将与之相反的时间段的特征否定掉就可以了。
集合概念推理：一个大的集合的两个方面形成对比，两者之间存在着互补性关系，也就是一个的增加意味着另一个的减少。
反之，相同。
在这里我们先来看一个例子：Passage：…The nineteenth century brought with it a burst of new discoveries and inventions that revolutionized the candle industry and made lighting available to all. In the early-to-mid-nineteenth century， a process was developed to refine tallow (fat from animals) with alkali and sulfuric acid. The result was aproduct called stearin. Stearin is harder and burns longer than unrefined tallow. This breakthrough meant that it was possible to make tallow candles that would not produce the usual smoke and rancid odor. Stearins were also derived from palm oils，so vegetable waxes as well as animal fats could be used to make candles...Which of the following can be inferred from paragraph 1 about candles before the nineteenth century?a.They did not smoke when they were burned.b.They produced a pleasant odor as they burned.c.They were not available to all.d.They contained sulfuric acid.正确答案是C.这一段的第一句就告诉我们：19世纪的一些新发明和发现也对蜡烛工业产生了一次巨大的革命，这次革命使得所有的人都使用上了照明。
托福阅读考试四种常见逻辑关系
托福阅读考试四种常见逻辑关系托福阅读考试四种常见逻辑关系逻辑关系是托福阅读题的一个重点考点，因此我们就必须要掌握一些常见的逻辑关系，下面店铺就来和大家说说吧!第一种因果关系因：because, because of, for, as, since, in that, on account of,with果：so, so that, therefore, thereby, as a result, hence, thus,consequently, accordingly因果关系除了传统意义上的显性因果表达词外，隐性的因果同样是不可忽略的一个重要部分。
隐性因果：A 导致(因-果)：cause, reason, lead to, give rise to, result in, render, make, let, ask, support,push, stimulate, spark, spur, fuel, produce, be responsible for如The increased pressures of expanding populations have led to the removal of woody plants sothat many cities and towns are surrounded by large areas completely lacking in trees and shrubs.在这段话中，有lead to, 表示了导致的意思，即结果; 而so that 更进一步表示了后面的结果，所以可以充分判定这段话有因果关系的.逻辑。
B 由…而来(果-因)：result from, derive from, originate from, initiate from, stem from, beresponsive to, be attributable to 如“The extreme seriousness of desertification results from the vast areas of land and tremendousnumbers of people affected, as well as from the great difficulty of reversing or even slowing theprocess.”在这段话中，根据result from可以推断出有因果关系，那如果是解释句子题时，选项中有因果关系就可以优先考虑。
快速突破托福阅读推断题之反推法
今天，针对托福阅读中的推断题，我们为大家详细介绍其中一个方法——反推法。
一般以下三种情况可以使用反推法：1、题干中问的信息与文中找到的信息互补的时候2、文中出现绝对词3、选项信息和文中信息互补且相反关于推断题出题方式：信号词:infer（推断）suggest（暗示）imply（暗示）问题：Which of the following can be inferred about X?The author of the passage implies that X…What does paragraph#suggest about X…选项特点：不会是原文明确表述的内容，但是通过原文信息一定可以被推断出来。
举个例子：我从今天开始再也不喝奶茶了。
以上这句话大家一般会推出：我在减肥or我最近嗓子不太好不过这些都不能成为正确的选项，真正的反推应该是我之前一定有在喝奶茶，这个其实是一个很典型的反推例子。
反推的核心逻辑如果A和C构成一个互补关系，那么它们具有的特征相反。
什么情况用反推之题干中问的信息与文中找到的信息互补的时候例题一：The story of the westward movement of population in the United States is,in the main,the story of the expansion of American agriculture—of thedevelopment of new areas for the raising of livestock and the cultivation ofwheat,corn,tobacco, and cotton.After1815improved transportation enabled more and more western farmers to escape aself-sufficient way of life and enter a national market economy.During periodswhen commodity prices were high,the rate of westward migration increasedspectacularly."Old America seemed to be breaking up and movingwestward,"observed an English visitor in1817,during the first greatwave of migration.Emigration to the West reached a peak in the 1830's.Whereasin1810only a seventh of the American people lived west of the AppalachianMountains,by1840more than a third lived there.What can be inferred from paragraph1about western farmers prior to1815?A.They had limited their crop production to wheat,corn,tobacco,and cotton.B.They were able to sell their produce at high prices.C.They had not been successful in raising cattle.D.They did not operate in a national market economy.这个问题是要我们推断1815年之前西方农民的相关信息，题中有一个比较明显的标志词就是prior to1815，也就是在1815年之前，但文章中给我们的是1815年之后的时间节点。
托福阅读推理题的正向推理与逆向推理
托福阅读推理题的正向推理与逆向推理托福阅读推理题是比较让童鞋们头疼的一类题型，它考察的内容多为隐藏在*里、需要根据*信息进行合理推测得出的结论，下面就和大家分享托福阅读推理题的正向推理与逆向推理，希望能够帮助到你们，快来一起学习吧。
托福阅读推理题的正向推理与逆向推理正向推理正向推理指的是最后的答案往往是和*所描述的内容一致的，而这种特征一般视为“整体”和“部分”的一致性，所以正向推理也被称为“整体与部分推理”。
正向推理包含两种主要情形，一种叫做给定段里面没有推理对象的情况，另外一种叫做有举例引发的“整体与部分推理”。
所谓“整体与部分推理”，就是*里面讲述一个特质是A，下面选项中的特征也是A，这个特质本身没有变化。
*里面讲什么特质，下面选项中就是什么特质，只不过一个是“整体”，一个是“部分”而已。
逆向推理“逆向推理”又叫“取非式推理”，*中讲的是A，下面选项里最终答案是“非A”，此推理包含三种情形。
1.由新时间点引发的逆向推理比如“now”表示现在，含有典型的暗转折含义。
事实上，凡是时间点概念，都暗示着转折。
比如说：1999年澳门回归了，这意味着1999年之前澳门没有回归。
这条原则可能听起来怪怪的，但意义重大，以后我们做托福*要比其他没有经历过严格训练的同学多长一个心眼，但凡是有时间点出现，就意味着前后的特质不一致，而这恰好是考点。
2.由新地点引发的逆向推理事实上，它和第一点的内涵是一致的，可以被统称为“分类取非”。
在*中经常会出现把一个大类分成两个小类的情况，比如*里面讲述生物分为两类，一类是动物，一类是植物，这时*里面会谈到动物和植物的“不同点”而不会是“相同点”。
3.由特定词引发的逆向推理这一类词包括unlike、without以及所有能够表示“比例”的词等。
一般推理题只要找准用来推理的句子，然后按照上面两种方法来做就不会有什么问题了。
只要掌握了这些技巧，当你在做托福阅读时，也能像侦探一样进行“推理”了。
托福备考经验：阅读推理题解题技巧
托福备考经验：阅读推理题解题技巧托福备考经验之具体解题思路1、一般对比推理：根据两个事情的对比特征，问其中一个事物的特征，只要将与之形成对比的另外一个事情的特征否定掉就可以。
2、时间对比推理：在这种推理中，一般有两个形成对比的时间段，它们所具有的特征一般相反。
当题干问一个时间段的特征时，只要将与之相反的时间段的特征否定掉就可以了。
3、集合概念推理：一个大的集合的两个方面形成对比，两者之间存在着互补性关系，也就是一个的增加意味着另一个的减少。
反之，相同。
这个比较抽象，我们来看一个例子：例如：Both the number and the percentage of people in the United States involved in nonagricultural pursuits expanded rapidly during the half century following the civil war, with some of the most dramatic increases occurring in the domains of transportation, manufacturing, and trade and distribution.What can be inferred from the passage about the agricultural sector of the economy after the Civil War?(A) New technological developments had little effect on farmers.(B) The percentage of the total population working in agriculture declined.(C) Many farms destroyed in the war were rebuilt after the war.(D) Farmers achieved new prosperity because of better rural transportation.文中指出：非农业人口的数量和比例都增加了。
托福阅读推断题：正逆向思维
托福阅读推断题：正逆向思维不同的同学有不同的擅长点，就像面对托福阅读一样，如果要说托福阅读的十种题型，对托福阅读的小结题和推断题，往往是要么因为时间，要么斟酌着不知道该选哪一项，从而大多数考生对这两种题型比较抗拒，下面我们就为大家分享一下如何用正逆向思维解决托福阅读推断题。
说到推断题，不要抗拒，更不要苦恼，虽然表面是推断题看着是云里雾里，但其实托福阅读没有你想像的那么难，因为托福作为标准化的考试，肯定会有一定的答题技巧，托福文章有很清晰的逻辑结构，每个自然段往往是按照TS (Topic Sentence) + SD (Supporting details)展开的，而文章多半是按Introduction + Aspects + Attitudes展开的。
只有明白了文章的写作思路才能更好更快的做对题目，作者必定是按照一定的行文顺序编排段落的，如果画一个水平轴作为事件发展的顺序，推断题是让你从这个轴上的某一个点去推测，无非就两个方向，顺着轴发展的方向或者逆着轴发展的方向，也就是我们接下来要说的用正向和逆向思维去解决推断题。
OG上将推断题定义为检查考生对文章中强烈建议但绝不明说观点(strongly implied but not explicitly stated in the text)的理解程度，属于理解性题目，题目要求如下：Paragraph 2 suggests which of the following about X?Which of the following can be inferred from paragraph 2 about X?According to paragraph 3, what do Y indicate about X?According to paragraph 4, what does the author imply about X?题干中有出现infer, imply, indicate或suggest这四个单词，我们就判定这个题目为推断题，那么推断题应该如何解答呢?第一步，判断题型。
逆向推理例子
逆向推理例子逆向推理是从结果推断出原因的思考方式。
最近，我曾经使用逆向推理通过解决一个难题的经历。
在一次比赛中，我们得到了一张包含100枚硬币的图片。
我们的任务是找出其中的假硬币，但我们没有任何其他信息。
最初，我们尝试分析图片上硬币的外观来判断，但这并没有帮助我们排除掉任何一个硬币。
然后，我开始使用逆向推理。
我想象着如果我是一个制造硬币的工人，并且有100枚完全相同的硬币，但其中有一个是假的，我会怎么做。
我会尝试让那个假硬币与其他硬币外观相同，但眼尖的顾客可能会发现它重量不同。
因此，我假设假硬币比其他硬币更轻。
这个假设可以帮助我们将硬币的数量减少一半。
接着，我想象着如果我是一个狡猾的制造商，我会将假硬币与其他的硬币外观和重量都做得一模一样。
但是，我会让它不同于其他硬币的东西肯定有一个。
这个时候我决定将硬币分成两组50枚硬币的组，然后将一组放在一个小秤上称重，再将另一组放在另一个秤上称重。
用逆向推理的方法我们就会发现其中一组的总重量会比另一组轻。
这样我们就可以把硬币的数量再次减半，直到我们找到那个假硬币。
使用逆向推理思考的关键是，你需要确保你的推理是正确的，这取决于你的假设。
如果你的假设是错误的，那么你就可能离正确答案越来越远。
在这个案例中，我的假设是正确的，因为假硬币确实比其他硬币轻。
但是，如果硬币的制作商使用比其他硬币重的材料来制作假硬币，那么我的推断将是不正确的。
综上所述，逆向推理是一种有用的思考方式，可以帮助我们解决难题和问题。
在我找到那枚假硬币的过程中，逆向推理发挥了关键作用。
我相信，在未来的学习和工作中，我会继续使用逆向推理，并将其作为一种重要的思考工具。
托福阅读推理题中那些“逆向推理”
托福阅读推理题中那些“逆向推理”(总3页)--本页仅作为文档封面，使用时请直接删除即可----内页可以根据需求调整合适字体及大小--托福阅读推理题中那些“逆向推理”托福阅读推理题每篇0-2道，考查学生理解和感知文章内容关系的能力，需要学生根据句子之间的逻辑性进行更深层次的推断。
有时候，我们可以利用“正向推理”：找出与文章描述特质一致的选项。
也有一些题，文章给我们的提示其实正是题干概念相反范畴的特质，这需要我们以此出发，逆推出题干范畴的特质，再得出答案。
那么，托福阅读推理题中会有哪些情况涉及“逆向推理”呢第一种情况：新的时间点引发的逆向推理例题一：来自-Petroleum Resources-第6题Paragraph 3: Oil pools are valuable underground accumulations of oil, and oil fields are regions underlain by one or more oil pools. When an oil pool or field has been discovered, wells are drilled into the ground. Permanent towers, called derricks, used to be built to handle the long sections of drilling pipe. Now portable drilling machines are set up and are then dismantled and removed. When the well reaches a pool, oil usually rises up the well because of its density difference with water beneath it or because of the pressure of expanding gas trapped above it. Although this rise of oil is almost always carefully controlled today, spouts of oil, or gushers, were common in the past. Gas pressure gradually dies out, and oil is pumped from the well. Water or steam may be pumped down adjacent wells to help push the oil out. At a refinery, the crude oil from underground is separated into natural gas, gasoline, kerosene, and various oils. Petrochemicals such as dyes, fertilizer, and plastic are also manufactured from the petroleum.of the following can be inferred from paragraph 3 about gushers○They make bringing the oil to the surface easier.○They signal the presence of huge oil reserves.○They waste more oil than they collect.○They are unlikely to occur nowadays.题目解析：选D. 在第三段中的第六句uAlthough this rise of oil is almost always carefully controlled today, spouts of oil, or gushers, were common in thepast.(虽然今天油上升到地表的过程被小心地控制着，但在过去自喷井是很常见的。
简要阐明逆向推理
简要阐明逆向推理逆向推理，也称为逆向推导，是一种推理方法，通过寻找问题的解决方案，来推断与问题有关的先决条件。
这种推理方式常常用于推断人类行为的起因、推断疾病的病因以及推断犯罪的犯罪动机等等，因此在诊断、犯罪侦查和心理学等领域得到了广泛应用。
逆向推理的基本思路是，设想问题的解决方案，然后分析解决方案所需要的先决条件是什么，从而得出问题的答案。
这个过程可以简单地概括为：问题（问题的解决方案）→ 先决条件（问题的答案）。
举个例子，如果你在街头看到一个人慢慢倒下，你会立即想到那个人可能晕倒了。
然后你会去找寻晕倒的原因：是否是因为那个人在太阳底下呆时间过长而受到中暑，或是因为他有某种疾病。
这个过程就是逆向推理，你设想了一个解决方案（那个人晕倒了），然后逆向地推导出了这个解决方案的先决条件（晕倒的原因）。
在医学领域，临床医生经常用逆向推理来诊断疾病。
例如，如果一个人有胸闷、呼吸困难和咳嗽等症状，医生会思考这些症状可能代表的疾病，然后通过进一步的检验和观察确认疾病的类型。
这个过程就是逆向推理，医生从病人身上找到了那个人可能存在的问题，然后逆向地推导出了这些问题的先决条件（病因）。
在心理学领域，逆向推理被用来推断一个人的动机。
例如，当要研究一个人为何会放弃一个非常好的工作，研究人员会思考这个人的动机，可能会考虑到那个人的工作不是很感兴趣，或是那个人缺乏工作上的支持，最后从中确认其动机。
这个过程同样也是逆向推理，研究人员从观察到的行为（放弃一个好工作）中推断出存在的问题，然后逆向推导出这些问题的先决条件（动机）。
总而言之，逆向推理是一种强大的推理方法，能够帮助我们推断各种问题的答案，因此在实际生活中，我们经常会用到逆向思维来解决一些难题。
托福考试阅读技巧 推断题如何解题
托福考试阅读技巧推断题如何解题推断题是托福阅读考试中的一个重要题型，想要在考试中少出错误，就需要在平时多看多练，掌握一些解题技巧。
托福考试阅读技巧一、逆向推断这类推断比较明显，往往在关键句当中有能利用的时间，地点，还有具体的取非词，找到之后针对该句的意思取个反就行。
1.The nineteenth century brought with it a burst of a new discoveries and inventions that revolutionized the candle industry and make lighting available to all. In the early-to-mid –nineteenth century, a process was developed to refine tallow with alkali and sulfuric acid. The result was a product called stearin.This breakthrough meant that it was possible to make allow candles that would not produce the usual smoke and rancid odor.Which of the following can be inferred from this paragraph about candles before the nineteenth century?A They did not smoke when they were burnedB They produced a pleasant odor as they burnedC They were not available to allD They contained sulfuric acid.这句话根据candles定位到第一句话，发现里面有the nineteenth century这个时间点，那题干问的是before the nineteenth century的情况，所以果断取个反选C2.This was before the steam locomotive, and canal building was at its height. The companies building the canals to transport coal needed surveyors to help them find the coal deposits worth mining as well as to determine the best courses for the canals. This job gave Smith an opportunity to study the fresh rock outcrops created by the newly dug canal. He later worked on similar jobs across the length and breadth of England, all the while studying the newly revealed strata and collecting all the fossils he could find. Smith used mail coaches to travel as much as 10,000 miles per year. In 1815 he published the first modern geological map, “A Map of the Strata of England and Wales with a Part of Scotland,” a map so meticulously researched that it can still be used today.Which of the following can be inferred about canal building?(2)○ Canals were built primarily in the south of England rather than in other regions.○ Canal building decreased after the steam locomotive was invented.○ Canal building made it difficult to study rock strata which often became damaged in the process.○ Canal builders hired surveyors like Smith to examine exposed rock strata.这道题同样根据canal building定位到第一句，在steam locomotive出现之前，cananl building一直是稳坐泰山的地位，而题干问现在canal building怎样，所以取个反，选B。
托福阅读中经常出现的四大逻辑关系
托福阅读中经常出现的四大逻辑关系逻辑关系(1):否定明显的否定：no, not, never, nor, none neither,deny隐含的否定：fail to, refuse, remove, miss, reject,absence of, lack of ,little,few例如：•I write to my parents every month.•I never fail to write to my parents every month.------------------------------------------------•He is little known as an artist.•He is not a famous artist否定前缀：o a-[asexual 无性别的]o ab-[abnormal非正常的]o anti-[antisocial 与社会对立的]o counter-[counterrevolution 反革命]o de-[decontrol解除管理, 解除管制]o dis- il- im- in- ir- mal- mis- non- un-...例如：•In fact, he was so quiet that his parents thought he was not normal.•In fact, he was so quiet that his parents thought he was abnormal.否定后缀：需注意的三个否定后缀：-less、-free、-proof•hatless: not wearing a hat•salt-free: without salt• a bulletproof car: a car designed not to be harmed by bullets双重否定：not fail to, not illegal, not uncommon, not unavailable逻辑关系(2):因果--明显因：because, because of, for, as, since, in that, on account of, with果:so, so that, therefore, thereby, as a result, hence, thus, consequently, accordingly逻辑关系(2):因果--隐藏1)表示“导致”的词(因-果)：cause, reason, lead to, give rise to, result in, render, make, let, ask, support,push, stimulate, spark, spur, prompt,fuel, produce, be responsible for/to如：•The increased pressures of expanding populations have led to the removal of woody plants so that many cities and towns are surrounded by large areas completelylacking in trees andshrubs。
托福阅读推理题题型介绍和解题思路实例讲解
托福阅读推理题题型介绍和解题思路实例讲解托福阅读题型中大部分题型都可以从原文中找到对应答案，但也有例外题型需要考生进行一定的逻辑推理分析才能得出正确答案，这种题型就是推理题。
今天给大家带来了托福阅读推理题题型介绍和解题思路实例讲解，下面就和大家分享，来欣赏一下吧。
托福阅读推理题题型介绍和解题思路实例讲解托福阅读推理题题型介绍1、时间对比推理在这种推理中，一般有两个形成对比的时间段，它们所具有的特征一般相反。
当题干问一个时间段的特征时，只要将与之相反的时间段的特征否定掉就可以了。
2、集合概念推理一个大的集合的两个方面形成对比，两者之间存在着互补性关系，也就是一个的增加意味着另一个的减少。
反之，相同。
3、一般对比推理在*中介绍事物1的特征，并给出了事物1、2的特征对比，然后问事物2的特征，解答题目时只要将事物1的特征否定掉就可以。
托福阅读推理题解题思路实例讲解遇到这类题型，考生先不要盲目看选项，而要有个大致的解题思路。
题干中一般给出关键词A，学生根据题目出现位置对应到段落，找到关键词所在句子;然后根据内容依据以上说明判断题目属于三种推理类型的哪一种;最后根据类型对应的解题方法答题。
实例解析The story of the westward movement of population in the US is, in the main, the story of the expansion of American agriculture of the development of new areas for the raising of livestock and the cultivation of wheat, corn, tobacco, and cotton. After 1815, improved transportation enabled more and more western farmers to escape a self-sufficient way of life and enter a national market economy during periods when commodity prices were high, the rate of westward migration increased spectacularly.What can be inferred from paragraph 1 about western farmers prior to 1815?A. They had limited their crop production to wheat, corn, tobacco and cotton.B. They were able to sell their produce at high pricesC. They had not been successful in raising cattle.D. They did not operate in a national market economy.思路分析根据题干关键词western farmers prior to 1815定位(重点关注年代)，可以看到关于“After 1815”的信息，这里就可以猜测解题用到时间对比。
技巧篇 如何巧用反义推理提升托福阅读速度
技巧篇：如何巧用反义推理提升托福阅读速度?如何巧用反义推理提升托福阅读速度?时间不够，无法阅读全文是很多考生在托福阅读中无法拿到高分的核心原因，但是直接做题又不知道选择的答案是否正确符合文章意思，这往往使得我们在备战阅读考试的效果大打折扣。
提高阅读速度是一个需要长期训练的过程，为了短期提高阅读分数和学习效果，三立在线小编带大家来对比一些方法来高效的发现题目的切入点并且解决问题拿到分数。
我们来直接看题：A symbiotic relationship is an interaction between two or more species in which one species lives in or on another species. There are three main types of symbiotic relationships: parasitism, commensalism, and mutualism. The first and the third can be key factors in the structure of a biological community; that is, all the populations of organisms living together and potentially interacting in a particular area.1. Which of the following statements about commensalism can be inferredfrom paragraph 1?○It excludes interactions betweenmore than two species.○It makes it less likely for specieswithin a community to survive.○Its significance to the organizationof biological communities is small.○Its role in the structure ofbiological populations is a disruptive one.✔解法1：初学者在看到这样题目的时候，会先把文章看完甚至翻译一遍，认为理解了自然就能选对答案。
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托福阅读推理题每篇0-2道，考查学生理解和感知文章内容关系的能力，需要学生根据句子之间的逻辑性进行更深层次的推断。
有时候，我们可以利用“正向推理”：找出与文章描述特质一致的选项。
也有一些题，文章给我们的提示其实正是题干概念相反范畴的特质，这需要我们以此出发，逆推出题干范畴的特质，再得出答案。
那么，托福阅读推理题中会有哪些情况涉及“逆向推理”呢?第一种情况：新的时间点引发的逆向推理例题一：来自-Petroleum Resources-第6题Paragraph 3: Oil pools are valuable underground accumulations of oil, and oil fields are regions underlain by one or more oil pools. When an oil pool or field has been discovered, wells are drilled into the ground. Permanent towers, called derricks, used to be built to handle the long sections of drilling pipe. Now portable drilling machines are set up and are then dismantled and removed. When the well reaches a pool, oil usually rises up the well because of its density difference with water beneath it or because of the pressure of expanding gas trapped above it. Although this rise of oil is almost always carefully controlled today, spouts of oil, or gushers, were common in the past. Gas pressure gradually dies out, and oil is pumped from the well. Water or steam may be pumped down adjacent wells to help push the oil out. At a refinery, the crude oil from underground is separated into natural gas, gasoline, kerosene, and various oils. Petrochemicals such as dyes, fertilizer, and plastic are also manufactured from the petroleum.6.Which of the following can be inferred from paragraph 3 about gushers?○They make bringing the oil to the surface easier.○They signal the pre sence of huge oil reserves.○They waste more oil than they collect.○They are unlikely to occur nowadays.题目解析：选D. 在第三段中的第六句uAlthough this rise of oil is almost always carefully controlled today, spouts of oil, or gushers, were common in thepast.(虽然今天油上升到地表的过程被小心地控制着，但在过去自喷井是很常见的。
)”，“today”时间点的出现提醒我们现在和过去的不同。
因此D选项正确。
这里文章中提到的特质“were common”是关于gushers在in the past的表现，而选项中的是说nowadays，逆推得到的选项。
第二种情况：新的地点引发的逆向推理例题二：来自-The Geologic History of the Mediterranean-第4题Paragraph 3: With question such as these clearly before them, the scientists aboard the Glomar Challenger processed to the Mediterranean to search for the answers. On August 23, 1970, they recovered a sample. The sample consisted of pebbles of hardened sediment that had once been soft, deep-sea mud, as well as granules of gypsum and fragments of volcanic rock. Not a single pebble was found that might have indicated that the pebbles came from the nearby continent. In the days following, samples of solid gypsum were repeatedly brought on deck as drilling operations penetrated the seafloor. Furthermore, the gypsum was found to possess peculiarities of composition and structure that suggested it had formed on desert flats. Sediment above and below the gypsum layer contained tiny marine fossils, indicating open-ocean conditions. As they drilled into the central and deepest part of the Mediterranean basin, the scientists took solid, shiny, crystalline salt from the core barrel. Interbedded with the salt were thin layers of what appeared to be windblown silt.4.Which of the following can be inferred from paragraph 3 about the solid gypsum layer?○It did not contain any marine fossil.○It had formed in open-ocean conditions.○It had once been soft, deep-sea mud.○It contained sediment f rom nearby deserts.题目解析：选A.根据本段倒数第三句“Sediment above and below the gypsum layer contained tiny marine fossils.(石膏层之上和之下的部分包含微小的海洋生物化石。
)”可以推断出石膏层不包含这样的化石。
本题就是从文章中关于其他地点：“之上和之下”的特质推断出题干概念范畴特质的例子。
第三种情况：特定词引发的逆向推理像是“unlike”“without”等词可以作为我们进行逆向推理的依据。
例题三:来自- The Origins of Cetaceans-第2题Paragraph 1: It should be obvious that cetaceans—whales, porpoises, and dolphins—are mammals. They breathe through lungs, not through gills, and give birth to live young. Their streamlined bodies, the absence of hind legs, and the presence of a fluke1 and blowhole2 cannot disguise their affinities with land dwelling mammals. However, unlike the cases of sea otters and pinnipeds (seals, sea lions, and walruses, whose limbs are functional both on land and at sea), it is not easy to envision what the first whales looked like. Extinct but already fully marine cetaceans are known from the fossil record. How was the gap between a walking mammal and a swimming whale bridged? Missing until recently were fossils clearly intermediate, or transitional, between land mammals and cetaceans.2. Which of the following can be inferred from paragraph 1 about early sea otters?○It is not difficult to imagine what they looked like.○There were great numbers of them.○They lived in the sea only.○They did not leave many fossil remains.题目解析：选A.定位到第4句“However, unlike the cases of sea otters and pinnipeds (seals, sea lions, and walruses, whose limbs are functional both on land and at sea), it is not easy to envision what the first whales looked like.”文章在描述cetaceans的特质之前，和“the cases of sea otters and pinnipeds”进行了一下对比，就是“unlike”，成为我们解题的依据。