搞定GMAT逻辑题必知的三条规律知多少

一、GMAT逻辑评价题做题思路
通常评价题的考题思维分为两种：Yes和No, 如果答案为Yes，那么我们就可以说，这个Yes回答是对段落推理过程的一种支持。如果答案为No, 则情况恰恰相反。很多情形下，评价题只是要求考生针对推理成立的隐含条件(假设)来判定一个最优选项，因此做题的关键要看考生能否在段落推理中找到这个逻辑(隐含)假设。
二、GMAT逻辑评价题例题分享：
Normally, the pineal gland governs a person’s sleep-wake cycle by secreting melatonin in response to the daily cycle of light and darkness as detected by the eye. Nonetheless, many people who are totally blind due to lesions in the visual cortex of the brain easily maintain a 24-hour sleep-wake cycle. So the neural pathway by which the pineal gland receives information from the eye probably does not pass through the visual cortex.
For purposes of evaluating the argument it would be most useful to establish which of the following?
(A) Whether melatonin supplements help people who have difficulty maintaining a 24-hour sleep cycle to establish such a pattern
(B) Whether the melatonin levels of most totally blind people who successfully maintain a 24-hour sleep-wake cycle change in response to changes in exposure to light and darkness
(C) Whether melatonin is the only substance secreted by the pineal gland
(D) Whether most people who do not have a 24-hour sleep-wake cycle nevertheless have a cycle of consistent duration
(E) Whether there are any people with normal vision whose melatonin levels respond abnormally to periods of light and darkness
三、GMAT逻辑评价题题目类型判断：
evaluate the argument
四、GMAT逻辑评价题题目翻译：
通常，PG通过分泌M来控制一个人的睡-醒循环，而M是眼睛所探测到的光暗的反应。然而，许多因为大脑视觉皮质受到损伤致盲的人可以很容易地维持24小时的睡-醒循环。所以，从眼睛到PG的神经传导可能不通过大脑的视觉皮质。以下哪一项最有助于评估这段论述的正确性?
五、GMAT逻辑评价题解题思路：
无既定思路，逐项分析。
六、GMAT逻辑评价题逐项分析：
A、M并非越多越好，补充M有可能导致过量，故无法得出确切结论，排除。
B、正确选项。符合题干主旨。
C、M是不是PG分泌的唯一物质。无关项。
D、没有24小时睡-醒循环的人是不是有他们特定的周期。无关项。
E、对光暗的异常可能有很多原因，不一定是视觉皮质引起的，排除。
七、GMAT逻辑评价题正确选项：
B。