解题方法：
　　* 定义结论句之因果关系
　　* 去除答案选项的whether后，当作weaken类型来做(80%以上的状况)
　　* 找答案选项yes or no与否，可weaken or support原题论述者
　　才3句话有点少……所以另外附上我自己的解题方法：
　　* 原推论的逻辑不完整，要加上选项的条件，才能合理推出结果。
　　* 句首的Whether不看;any改many，用有关、无关来筛选答案。正确答案通常能支持或否定推论;错误答案不是移焦，就是无关。
　　* 正确答案只需评估原文推论的正确性，至于Whether的结果是Yes或No并不重要。
　　例题讲解：
　　OG12-CR-12
　　A certain automaker aims to increase its market share by deeply discounting its vehicles' prices for the next several months. The discounts will cut into profits, but because they will be heavily advertised the manufacturer hopes that they will attract buyers away from rival manufacturers' cars. In the longer term, the automaker envisions that customers initially attracted by the discounts may become loyal customers.
　　In assessing the plan's chances of achieving its aim, it would be most useful to know which of the following?
　　首先看题目：
　　(1)某公司试图通过降价吸引客户
　　(2)虽然折扣会削减profit，但是某公司希望借助这个降价折扣将消费者从竞争者那里吸引过来，并成为忠诚客户
　　然后题目问的是下面哪个信息对于evaluate这个计划最重要。
　　(A)Whether the automaker's competitors are likely to respond by offering deep discounts on their own
　　products?
　　正解。这个选项的意思是：这个公司的竞争对手会不会对自己的产品降下更大的折扣?如果一个企业想通过降价来吸引客户的话，它就必须保证自己产品在质量不变的基础上降价之后价格比其他家产品的要低廉。但是如果竞争对手也降价，而且降价幅度更大的话，设想的一切都没了。用上面的方法来看，去掉whether之后就是竞争对手会打折打得更狠，weaken了题目的中心论点。
　　另外在这里引用hispeed版主的点评：
　　你们这些天真的制造商以为降价就可以吸引顾客么，太天真了!>_
　　(B)Whether the advertisements will be created by the manufacturer's current advertising agency?
　　本选项的意思是：这个公司现在用的广告团队会如何打广告?无关选项。因为题目中根本就没有提到广告方面的因素。
　　(C)Whether some of the automaker's models will be more deeply discounted than others?
　　本选项的意思是这家公司的某些车型是否会打折更猛?都是自己的车根本就不用纠结这个问题。题目的关键是打折之后是否会比竞争对手的车便宜，不是自家内部比来比去。
　　(D)Whether the automaker will be able to cut costs sufficiently to maintain profit margins even when the
　　discounts are in effect?
　　本选项的意思是打折见效之后这家公司能不能有效的削减成本来保持profit?无关选项。题目中心是借打折吸引客户，至于成本和profit的问题以后再说。
　　(E)Whether an alternative strategy might enable the automaker to enhance its profitability while holding a constant or diminishing share of the market?
　　本选项的意思是这家公司会不会有一些alternative的战略在hold住market share额同时提高利润?这个选项与上个选项一样都是转移焦点，题目谈论的是能否吸引客户并且让他们变成loyalty customers，高利润神马的暂时都不考虑。所以无关。
　　OG12-CR-74
　　In the past the country of Malvernia has relied heavily on imported oil. Malvernia recently implemented a program to convert heating systems from oil to natural gas. Malvernia currently produces more natural gas each year than it uses, and oil production in Malvernian oil fields is increasing at a steady pace. If these trends in fuel production and usage continue, therefore, Malvernian reliance on foreign sources for fuel is likely to decline soon.
　　Which of the following would it be most useful to establish in evaluating the argument?
　　首先看题：
　　(1)过去的时候M国非常依赖进口石油，但是M国最近实施了一个program就是将供热系统从使用石油转换成使用天然气
　　(2)M国的天然气资源供大于求，而石油产量也在稳步上升
　　结论：如果M国能源产量持续这个趋势的话，那么M国对进口燃料的依赖将会下降。
　　(A) When, if ever, will production of oil in Malvernia outstrip production of natural gas?
　　本选项说的是什麼時候M国的石油产量会超过天然气产量，题目的中心论点是M国对进口燃料的依赖是否会下降，所以说要比也不是石油和天然气产量比，因此无关。
　　(B) Is Malvernia among the countries that rely most on imported oil?
　　本选项说M国是否是所有的国家中最依赖进口石油的?题目中并没有提到其他国家，故和A选项一样，这个选项也属于错误对比。
　　(C) What proportion of Malvernia's total energy needs is met by hydroelectric, solar, and nuclear power?
　　本选项说氢电、太阳能和核能在M国的能源使用中占多大的比例?此选项同B。因为题目中并没有提到除了石油和天然气之外的其他的能源，所以也是错误对比的无关选项。
　　(D) Is the amount of oil used each year in Malvernia for generating electricity and fuel for transportation increasing?
　　正解。本选项说M国用于交通方面和发电方面的石油是否增加?这个选项可以说是填补了题目的一个gap，因为就算M国供热系统需要的石油减少但是用于其他方面的石油量上升的话，那么还是要依赖进口的。如果将这个问题变成陈述的话，即：M国用于交通方面和发电方面的石油需求量上升，那么是会削弱结论的。
　　(E) Have any existing oil-burning heating systems in Malvernia already been converted to natural-gas-burning heating systems?
　　本选项说：M国是否已经有烧石油的供暖系统转换成天然气系统了?这个选项虽然相关，但是题目已经说了这个系统迟早会转换成天然气，所以这个选项不具备evaluate的资格。
　　练习：
　　TN-5-Q38:
　　Journalist: Well-known businessman Arnold Bergeron has long been popular in the state, and he has often talked about running for governor, but he has never run. However, we have just learned that Bergeron has fulfilled the financial disclosure requirement for candidacy by submitting a detailed list of his current financial holdings to the election commission. So, it is very likely that Bergeron will be a candidate for governor this year.
　　The answer to which of the following questions would be most useful in evaluating the journalist’s argument?
　　A. Has anybody else who has fulfilled the financial disclosure requirement for the upcoming election reported greater financial holdings than Bergeron?
　　B. Is submitting a list of holdings the only way to fulfill the election commission’s financial disclosure requirements?
　　C. Did the information recently obtained by the journalists come directly from the election commission?
　　D. Have Bergeron’s financial holdings increased in value in recent years?
　　E. Had Bergeron also fulfilled the financial disclosure requirements for candidacy before any previous gubernatorial elections?
　　TN-11-Q3.
　　Scientists have made genetic modifications to cotton to increase its resistance to insect pests. According to farmers’ report, the amount of insecticide needed per acre to control insect pests was only slightly lower for those who tried the modified seed than for those who did not. Therefore, since the modified seed costs more than ordinary seed without producing yields of higher market value, switching to the modified seed would be unlikely to benefit most cotton farmers economically.
　　Which of the following would it be most useful to know in order to evaluate the argument?
　　A. Whether farmers who tried the modified cotton seed had ever tried growing other crops from genetically modified seed.
　　B. Whether the insecticides typically used on ordinary cotton tend to be more expensive than insecticides typically used on other crops.
　　C. Whether for most farms who grow cotton it is their primary crop
　　D. Whether the farmers who have tried the modified seed planted as many acres of cotton, on average, as farmers using the ordinary seed did.
　　E. Whether most of the farmers who tried the modified seed did so because they had previously had to use exceptionally large quantities of insecticide.
　　以上内容对GMAT逻辑考试中的常见题型及解题技巧进行了详细的讲解，考生可以根据文中重点进行针对性的练习，掌握并熟练应用GMAT逻辑试题的解题思路，从而在GMAT考试中取得好成绩。