在托福閱讀的課程中，常常被同學們問到的是如何提高閱讀和做題效率的問題，因為大部分同學無法拿到閱讀高分的核心原因是時間不夠無法讀全文章，直接做題又感覺患得患失地不知道選擇的答案是否正確符合文章意思，這往往使得我們在備戰閱讀考試的效果大打折扣。
由于提高閱讀速度是一個需要長期訓練的過程，為了讓同學們短期提高一些閱讀分數和學習效果，我們來試試對比一些方法來高效的發現題目的切入點并且解決問題拿到分數。
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：
初學者在看到這樣題目的時候，會先把文章看完甚至翻譯一遍，認為理解了自然就能選對答案。這是正確率最高最靠譜的做法，但最大的缺陷是考試時無法在短時間內理解文章并且做完題目。所以在閱讀能力不是很強的時候，盡量不要使用看完理解再做題的方法。
?解法2：
定位規律
? 題干關鍵詞：commensalism
? 文中定位點：There are three main types ofsymbiotic relationships: parasitism, commensalism,and mutualism.有三種共生關系：寄生、共生、互利共棲。說的是題干關鍵詞本身的內容，無法對應選項。
? 再往后讀啊讀啊讀啊……理論上來說看到這里應該能得到答案了，但是……但是……看看選項？
○共生關系不包括超過兩個物種之間的相互作用
○共生關系使得物種在生物團體中難以生存
○共生關系在生物群體中的重要性是小的
○共生關系在生物結構中的角色是引起混亂的
選哪個？！正確答案是哪個啊？
這里我們要學的是一個小套路，我們把文中內容和選項都理解后得到這樣的一個邏輯：
文章：第一個和第三個在一個生物團體結構中是重要的；意思是，所有的有機體居住在一起并且在特定的區域相互作用。
推理模式：第一個（寄生）和第三個（互利共棲）在一個生物團體結構中是重要的→第二個（共生）是不重要的
?所以選C
這個切入點你發現了嗎？
但這樣分析題目，對我們來說有什么實際的意義呢？同學們，這篇文章的核心就是希望大家能高效的發現題目的切入點并且解決問題。于是，對于這道題來說發現一個能夠廣泛使用的規律，比起選出正確答案更有意義：
讓我們聊聊剛才在題目中的推理模式：第一個（寄生）和第三個（互利共棲）在一個生物團體結構中是重要的→第二個（共生）是不重要的。
這個推理模式我叫做反義推理（有些老師也叫做反向推理、取非，意思一致），是托福閱讀推理題常用的推理模式，并且在細節題、否定事實信息題（NOTEXCEPT）和判斷其他題型錯誤選項的時候經常使用，也是最常見的一種思維模式。反義推理的核心來自于歸約（reduction），意思是當未知量與已知量看上去無法匹配的時候，在二者之間搭上一個橋梁來使得找答案變得更簡單。
讓我們來看看類似題目中用到反義推理的高效表現
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 mighthave 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 wind blown silt.
4．Which of the following can beinferred 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 from nearby deserts.
?解析：
這道題很容易，和上一題是同樣的套路
? 題干關鍵詞：the solid gypsum layer
? 文中定位點：Sediment above and below the gypsumlayer contained tiny marine fossils, indicating open-ocean conditions.
? 利用反義推理：在石膏層上面和下面的沉積層中包含小海洋化石→石膏層不包含海洋化石
?所以選A
而在我們熟練了在一個完整概念下不同因素之間的反義推理后（例如整體是【A,B,C】, 文中說AB重要則C不重要，AB有東西則C沒有），將完整概念拓展到時間點前后區分概念會使得做題變得更加的簡單：
【Paragraph 2】Yet this most fundamental standard of historical periodization concealsa host of paradoxes. Nearly every movie theater, however modest, had a piano ororgan to provide musical accompaniment to silent pictures. In many instances,spectators in the era before recorded sound experienced elaborate auralpresentations alongside movies' visual images, from the Japanese benshi(narrators) crafting multivoiced dialogue narratives to original musicalcompositions performed by symphony-size orchestras in Europe and the UnitedStates. In Berlin, for the premiere performance outside the Soviet Union of TheBattleship Potemkin, film director Sergei Eisenstein worked with Austriancomposer Edmund Meisel (1874-1930) on a musical score matching sound to image;the Berlin screenings with live music helped to bring the film its wideinternational fame.
5. Paragraph 2 suggests which of the following about Eisenstein’s film The Battleship Potemkirf?
○The film was not accompanied by sound before its Berlin screening.
○The film was unpopular in the Soviet Union before it was screened in Berlin.
○Eisenstein’s film was the first instance of collaboration between a director and a composer.
○Eisenstein believed that the musical score in a film was as important as dialogue.
?解析：
? 題干關鍵詞：Eisenstein’s film The Battleship Potemkirf，大寫字母很容易找
? 文中定位點：In Berlin, for the premiereperformance outside the Soviet Union of The Battleship Potemkin, film directorSergei Eisenstein worked with Austrian composer Edmund Meisel (1874-1930) on amusical score matching sound to image; the Berlin screenings with live musichelped to bring the film its wide international fame.
? 利用反義推理：在柏林首次公演→在柏林之前沒有演過
?所以選A
對我們來說，掌握了時間點前后不一致，可以使用反義推理這個方法，能讓我們更快的得到答案：
The areas covered by this material were so vast that the ice that deposited it must have been a continental glacier larger than Greenland orAntarctica. Eventually, Agassiz and others convinced geologists and the general public that a great continental glaciation had extended the polar ice caps far into regions that now enjoy temperate climates. For the first time, peoplebegan to talk about ice ages. It was also apparent that the glaciation occurred in the relatively recent past because the drift was soft, like freshly deposited sediment. We now know the age of the glaciation accurately from radiometric dating of the carbon-14 in logs buried in the drift. The drift ofthe last glaciation was deposited during one of the most recent epochs of geologic time, the Pleistocene, which lasted from 1.8 million to 10,000 yearsago. Along the east coast of the United States, the southernmost advance ofthis ice is recorded by the enormous sand and drift deposits of the terminal moraines that form Long Island and Cape Cod.
5.It can be inferred from paragraph 2 that Agassiz and other geologistsof his time were not able to determine
○which geographic regions had beencovered with ice sheets in the last ice age
○the exact dates at which drifts hadbeen deposited during the last ice age
○the exact composition of the driftslaid during the last ice age
○how far south along the east coastof the United States the ice had advanced during the last ice age
?解析：
? 題干關鍵詞：Agassiz and other geologists of histimewere not able to determine
? 文中定位點：We now know the age of theglaciation accurately from radiometric dating of the carbon-14 in logs buriedin the drift.
? 利用反義推理：Wenow know ……→Agassiz and other geologists of histimewere not able to determine
?所以選B
It was not until the Cambrian period, beginning about 600 million yearsago, that a great proliferation of macroscopic species occurred on Earth andproduced a fossil record that allows us to track the rise and fall ofbiodiversity. Since the Cambrian period, biodiversity has generally risen, butthere have been some notable exceptions. Biodiversity collapsed dramaticallyduring at least five periods because of mass extinctions around the globe. Thefive major mass extinctions receive most of the attention, but they are onlyone end of a spectrum of extinction events. Collectively, more species wentextinct during smaller events that were less dramatic but more frequent. Thebest known of the five major extinction events, the one that saw the demise ofthe dinosaurs, is the Cretaceous-Tertiary extinction.
2. Paragraph 1 supports which of the following statements about life onEarth before the Cambrian period?
○Biodiversity levels were steady, asindicated by the fossil record.
○Levels of biodiversity could not betracked.
○The most dramatic extinction episodeoccurred.
○Few microscopic species existed.
?解析：
? 題干關鍵詞：before the Cambrian period?
? 文中定位點：It was not until the Cambrian period, beginning about 600 million years ago, that a great proliferation ofmacroscopic species occurred on Earth and produced a fossil record that allowsus to track the rise and fall of biodiversity.
? 利用反義推理：It was not until the Cambrian period……allows us to track the riseand fall of biodiversity→Levels of biodiversity could not betracked.
?所以選B
反義推理這個模式還可以被用在NOTEXCEPT題當中：
Five centuries later, about 7700B.C., a new village rose on the mound.At first the inhabitants still hunted gazelle intensively. Then, about 7000B.C., within the space of a few generations, they switched abruptly to herdingdomesticated goats and sheep and to growing einkorn, pulses, and other cerealgrasses. Abu Hureyra grew rapidly until it covered nearly 30 acres. It was aclose-knit community of rectangular, one-story mud-brick houses, joined bynarrow lanes and courtyards, finally abandoned about 5000 B.C.. Many complexfactors led to the adoption of the new economies, not only at Abu Hureyra, butat many other locations such as 'Ain Ghazal, also in Syria, where goat toebones showing the telltale marks of abrasion caused by foot tethering (binding)testify to early herding of domestic stock.
10.According to paragraph 5, after 7000 B.C. the settlement of AbuHureyra differed from earlier settlements at that location in all of thefollowing EXCEPT
○the domestication of animals
○the intensive hunting of gazelle
○the size of the settlement
○the design of the dwellings
?解析：
? 題干關鍵詞：after 7000 B.C
? 文中定位點：Then, about 7000 B.C……但我的思考是，之后的內容對應選項則會成為正確的內容，而題目需要我們找到錯誤的內容并且選出來，那么，7000BC之前的內容如果對應選項，就應該是錯誤的并且可以被選出來了，根據這個想法我們往前看
? Five centuries later, about7700B.C., a new village rose on the mound. At first the inhabitants stillhunted gazelle intensively.
?對應答案B
During wakefulness, breathing is controlled by two interacting systems.The first is an automatic, metabolic system whose control is centered in thebrain stem. It subconsciously adjusts breathing rate and depth in order toregulate the levels of carbon dioxide (CO2) and oxygen (O2), and the acid-baseratio in the blood. The second system is the voluntary, behavioral system. Itscontrol center is based in the forebrain, and it regulates breathing for use inspeech, singing, sighing, and so on. It is capable of ignoring or overridingthe automatic, metabolic system and produces an irregular pattern of breathing.
2.According to paragraph 2, all of the following are true of thevoluntary breathing system EXCEPT:
○It has its control center in thebrain stem.
○It controls breathing for a numberof activities during wakefulness.
○It is able to bypass the automatic system.
○It produces an irregular breathing pattern.
?解析：
? 題干關鍵詞：the voluntary breathing system
? 文中定位點：The second system is the voluntary,behavioral system.
? 反義推理：看到second則一定有first，思考是first的內容對應選項則一定不符合second的內容所以文中The first is an automatic, metabolic systemwhose control is centered in the brain stem.
