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

　　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。

　　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.After 1815improved 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 in 1817, during the first greatwave of migration. Emigration to the West reached a peak in the 1830's. Whereasin 1810 only a seventh of the American people lived west of the AppalachianMountains, by 1840 more than a third lived there.

　　What can be inferred from paragraph 1 about western farmersprior 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 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 to 1815，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。这个时候是不是符合刚刚说的题干中问的信息和在文中找到的信息，构成了一个互补关系的时候？那我们来看一下1815年之后这句话说了什么。

　　After 1815improvedtransportation enabled more and more western farmers to escape a self-sufficient way of life and enter a national market economy.

　　不断改进的交通，使得越来越多的农民逃脱原本自给自足的生活方式，然后进入了一个全国性的市场经济。

　　这也意味着1815年之前的农民和1815年之后的农民，他们所具有的特征是相反的，所以我们就可以选到D选项了。

　　例题二：

　　Another theory, known as broken-forest hypothesis, speculates that animals in Southeast Asia must risk descending to the ground or glide to move between trees because the top layer of the forest-the treecanopy-has fewer woody vines connecting tree crowns in Southeast Asian forests than in New World and African forests. It also presumes that the tree canopy in Asian forests is more uneven in height, due to the existence of tall dipterocarp trees with lower trees between them, and this imbalance is favored by gliding animals.

　　Paragraph 3suggestswhich of the following ideas about forests in which there are abundant woody vines connecting tree crowns?A. There are likely fewer predators on the ground in such forests than in other forests.B. In such forest, the tree canopy is more even than that in other forests.

　　C. In such forest, there is a wider diversity of animals than other forests.

　　D. Animals in such forests can move between trees by traveling on vines.

　　这道题问的是很多连接树冠的树蔓的森林的特征，不过，文章给的是有很少的woody vines的森林的特征。这道题又是题目中问的信息和文中给到的信息不是同一个但具有互补的关系。那我们来看看有很少woody vines的去森林有什么特征呢？

　　Another theory, known as broken-forest hypothesis,speculatesthatanimals in Southeast Asia must risk descending to the ground or glide to movebetween trees because the top layer of the forest-thetreecanopy-has fewer woody vinesconnecting tree crowns in Southeast Asian forests than inNew World and African forests.

　　另一个理论推测，由于树林上面有很少的woody vines连接树冠，所以东南亚的动物必须冒险降落地面或者在树与树之间滑行。

　　所以，如果树上有很多很多的woody vines，那动物们就可以通过woody vines穿梭树林，不需要冒险降落或者滑翔了，所以我们就可以选到D选项了。

　　文中出现绝对词

　　比如most，only，mostly

　　例题一：

　　What caused these extinctions? Why did these extinctions eliminatemostlylarge mammals? Why were the extinctions most severe in Australia and the Americas? No completely satisfactory explanation exists, but two competing hypotheses are currently being debated. One holds that rapid climatic changes at the end of the Pleistocene caused extinctions, whereas another, called prehistoric overkill, holds that human hunters were responsible.

　　What can be inferred from paragraph 1 about the extinctions that occurred at the end of the Pleistocene?

　　A. They were caused by a single factor.B. They had relatively little impact on small mammals.

　　C. They wiped out nearly all of the world's large mammal species.

　　D. They occurred slowly over a period of thousands of years.

　　这道题问的是在Pleistocene末期的灭绝能推断出什么内容，文章从一开始就讲什么导致了灭绝？为什么灭绝的主要是大型哺乳动物？这里出现了第一个绝对词mostly，言外之意就是除了大型哺乳动物以外的其他哺乳动物没怎么被杀掉，我们就可以选到B选项了。

　　选项信息和文中信息互补且相反

　　例题一：

　　One innovation was a new plow, with a curved attachment(moldboard) to turn over wet, heavy soils, and a knife (or coulter) in front ofthe blade to allow a deeper and easier cut. This more complex plow replaced thesimpler “scratch” plow that merely made a shallow, straight furrow in theground.In the lands around the Mediterranean, with light rains and mildwinters, this had been found, but in the wetter terrain north and west of theDanube and the Alps, such a plow left much to be desired, and it is to bewondered if it was used at all.Cleared lands would more likely havebeen worked by hand tilling, with little direct help from animals, and the vastforests natural to Northern Europe remained either untouched, or perhapscleared in small sections by fire, and the land probably used only so long asthe ash-enriched soil yielded good crops and then abandoned for some otherssimilarly cleared field. Such a pattern of agriculture and settlement was no basisfor sustainedcultural or economic life.

　　Paragraph 1 implies which of the following about agriculture before the introduction of the new plow?

　　A. Limited rainfall had prevented large-scale agriculturaldevelopment.B. Most of Europe’s developed agricultural communities were located in the south.C. Several other important innovations immediately preceded the development ofthe new plow.

　　D. Much of Europe’s forestland had been converted to agricultural use.

　　这道题问关于在新犁引进之前的农业，那我们需要去找新犁引进之前的农业的相关信息。

　　段落第一句话就讲了新犁这可以去翻那些很湿很重的土，同时挖地更深更加容易，不过这句话本身可以用来做反推的，但是没有出相关的选项。

　　那我们继续往下看第二句话，在Mediterranean这种雨比较少、冬天比较温和的地方老犁是可以用的，但在西边和北边比较潮湿的地方就不能用了，只能靠手和动物，大部分的森林维持一个没有被动过的状态或者火烧了了其中的一小块，农民用完这块土地后再去用别的新的土地。

　　所以，我们看B选项，文章说在北边和西边因为土地潮湿，犁不能使用，那里的人靠的是一种比较原始的耕作方式，所以除了北边和西边的其他区位会更加的先进，B选项中的“南方”与文中提供的信息满足互补且相反的关系，所以是正确选项。

　　错误选项辨析原则

　　不相关的信息不能选

　　反的信息不能选

　　不存在的逻辑关系不能选

　　第三种情况，虽然选项它符合反推这个逻辑，但是很多同学如果心里不确定的话，我们可以使用这个错误选项辨析的原则来帮助我们排除其他的选项，然后最后去选择符合反推逻辑的选项。

　　通过通通老师的详细讲解

　　是否对于使用反推法的三大情况

　　完全的掌握辽？

　　除了反推法

　　关于托福阅读推断题

　　你还知道其他适用的方法嘛？

　　可在文末留言与我们分享哦~

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