做逻辑题建议先读题干，再看文章。最重要的是在文章中找到Core Argument。在读文章时，要特别注意其中出现的since, because, if等表示命题之间的因果、条件关系的词汇，也要注意句子的谓语部分出现的表示相关和因果关系的词汇，例如correlate with, coincide with，这些词汇构成了Core Argument。
Which one of the following, if true, most strengthens the argument?
Which of the following, if true, would support the author’s hypothesis?
Sparva, unlike Treland’s other provinces, requires automobile insurers to pay for any medical treatment sought by someone who has been involved in an accident; in the other provinces, insurers pay for nonemergency treatment only if they preapprove the treatment. Clearly, Sparva’s less restrictive policy must be the explanation for the fact that altogether insurers there pay for far more treatments after accidents than insurers in other provinces, even though Sparva does not have the largest population.
7. Which of the following, if true, most strengthens the argument?
A Car insurance costs more in Sparva than in any other province.
B The cost of medical care in Sparva is higher than the national average.
C Different insurance companies have different standards for determining what constitutes emergency treatment.
D Fewer insurance companies operate in Sparva than in any other province.
E There are fewer traffic accidents annually in Sparva than in any of the provinces of comparable or greater population.
Which of the following, if true, would most seriously weaken/undermine/cast doubt on the author’s assertion?
In 1998 the United States Department of Transportation received nearly 10,000 consumer complaints about airlines; in 1999 it received over 20,000. Moreover, the number of complaints per 100,000 passengers also more than doubled. In both years the vast majority of complaints concerned flight delays, cancellations, mishandled baggage, and customer service. Clearly, therefore, despite the United States airline industry’s serious efforts to improve performance in these areas, passenger dissatisfaction with airline service increased significantly in 1999.
21. Which of the following, if true, most seriously weakens the argument?
A Although the percentage of flights that arrived on time dropped slightly overall, from 77 percent in 1998 to 76 percent in 1999, some United States airlines’ 1999 on-time rate was actually better than their 1998 on-time rate.
B The number of passengers flying on United States airlines was significantly higher in 1999 than in 1998.
C Fewer bags per 1,000 passengers flying on United States airlines were lost or delayed in 1999 than in 1998.
D The appearance in 1999 of many new Internet sites that relay complaints directly to the Department of Transportation has made filing a complaint about airlines much easier for consumers than ever before.
E Although the number of consumer complaints increased for every major United States airline in 1999, for some airlines the extent of the increase was substantial, whereas for others it was extremely small.
assumption/explain the difference/reconcile the discrepancy/resolve the paradox
除了逻辑强化与弱化，逻辑单题也经常问到原文论证或理论的假设(assumption)。假设，按其定义，指的是如其不成立，则原推理不成立的条件，这时，答案要提供一个桥梁，连接推理的两端，好比bridge the gap。
另一种考法是，原文两个命题之间存在语言上的矛盾，比如，A句说某事物增加，B句说另一个相关事物减少。题干要求解释原文两个说法A和B之间的差别：explain the difference, 或者，由于A、B在这种情况下彼此似乎冲突，题干就问如何调节这种差异或冲突：reconcile the discrepancy, 或者解决或消除这种冲突或矛盾：resolve the paradox。这时的答案不能重复A或B，而是提供中间环节X，使得A→X→B。
During the day in Lake Constance, the zooplankton D. hyalina departs for the depths where food is scarce and the water cold. D. galeata remains near the warm surface where food is abundant. Even though D. galeata grows and reproduces much faster, its population is often outnumbered by D. hyalina.
3. Which of the following, if true, would help resolve the apparent paradox presented above?
A The number of species of zooplankton living at the bottom of the lake is twice that of species living at the surface.
B Predators of zooplankton, such as whitefish and perch, live and feed near the surface of the lake during the day.
C In order to make the most of scarce food resources, D. hyalina matures more slowly than D. galeata.
D D. galeata clusters under vegetation during the hottest part of the day to avoid the Sun’s rays.
E D. galeata produces twice as many offspring per individual in any given period of time as does D. hyalina.
Bridge the gap: predators在湖表面吃掉g，导致g的数量下降，尽管g生存条件好，繁殖能力强，但是面临众多捕食者，后代数量必定下降，反倒不如生存条件差，但没有天敌的h，完美解决了paradox，所以选B。A的意思是h的数量是g的两倍，h本来就多，所以这个是加强paradox的;C的意思是h比g成熟慢，说明h的数量比g少，而文章得出结论h > g，与文章不符，同理，D和E也是可以得出g > h，与文章不符。
3. Out of Scope：扩大了argument的范围