GRE阅读中的削弱题是一直是学生比较头疼的一类题目。这类题目在逻辑单题中占的比重最大，并且在阅读文章中也有考察。最近在梳理新题库的时候，我发现削弱题依然是逻辑单题中占比最大的一类题目，并且是更新最多的一类题目。今天就跟我一起来看看削弱题的做法吧！
削弱题通常是削弱结论，题目上一般的表述是：Which of the following, if true, most seriously undermines/doubts/
weakens the argument?
针对这类题目，光是靠读懂文章，肯定是不行的。我们通常会告诉学生按照以下的解题步骤来做题：
Step1：
首先要找出结论是什么，通常结论出现的标志词有：It must be/It follows/It cannot be/It is bound to等，总之结论一定是对某一事物进行判断或预测，为文章的主要观点；
Step2：
找出论据是什么，也就是文章是基于什么样的原因得出了第一步中说的结论；
Step3：
接下来有三种方法进行解题，让我们结合具体题目进行分析：
方法1：破坏论证假设
破坏得出文章结论所基于的前提假设（也就是在Step2中找出的论据中的前提假设），可以是找出假设中的漏洞，也可以是直接对假设进行取反，这样就削弱了结论。
例：A对B说，我只考了89分，你不可能考90分，那这里A得出结论基于的前提假设是认为自己的成绩高于或等于B的成绩，我们可以对这个假设取反或找出其中的漏洞，比如选项中说B最近成绩突飞猛进，早已在不知不觉中反超A了，这样的选项可为正确答案。
以下面的这个题为例：
The Great Sphinx is a huge statue in Egypt that has a lion’s body with a man’s head. The face of the Sphinx has long been claimed to be that of pharaoh Khafre, who lived around 2600 B.C., but it cannot be: erosion patterns recently discovered on the lion’s legs can only have been caused by heavy rains, and the Sahara has not had heavy rains in over 10,000 years.
Which of the following, if true, most seriously weakens the argument?
A. The face of the Sphinx bears a resemblance to the faces on certain stylized statues dating from both before and after the reign of Khafre.
B. Other erosion patterns that appear on the body of the Sphinx are of a sort that could be caused by wind and sand alone
C. Other than the Sphinx, there are no surviving sculptures that have been claimed to portray the face of Khafre.
D. In the last 10,000 years the climate of Egypt has been so dry that even rains that are not heavy have been extremely infrequent.
E. The face of the Sphinx is small relative to the rest of the head, indicating that the face may have been recarved long after the Sphinx was built.
文章翻译：狮身人面像是在埃及的一个有着狮子身子和人头的大型雕像。狮身人面像的脸长期以来被认为是大约生活在公元前2600年的Khafre法老的，但是这不可能：因为狮子腿上的腐蚀只有可能来自于暴雨，而撒哈拉地区已经有超过10000年没有过暴雨了。首先需要找出文章的结论是什么，这里的结论是The Great Sphinx的脸不可能是Khafre法老的。其次分析论据，这里的论据是因为狮子被腐蚀已经有超过10000年的历史了。对这个逻辑框架进行解读就是：
这里基于的前提假设是脸的建造时间要早于或等于身子，对这里的前提假设取反，正确选项应该是脸的建造时间晚于身子，所以选E。
这个方法你学会了吗？我们拿一道题来练习一下吧！
A photograph from 1843 is sometimes claimed to be the earliest surviving portrait of Abraham Lincoln (1809-1865), sixteenth President of the United States. The photograph shows a face without a cleft chin, whereas Lincoln’s chin was cleft. However, since skilled retouching of a photographic negative can undetectably change a feature such as a cleft chin in portraits produced from the negative, absence of a cleft chin is inconclusive as evidence that the photograph is not Lincoln.
7. Which of the following, if true, most seriously undermines the argument
A. Few of the authenticated photographs of Lincoln show his cleft chin, since during his presidency (1860-1865) he was bearded.
B. An authenticated photograph of Lincoln taken in 1846 clearly shows a cleft chin.
C. The photograph was made by the daguerreotype process, an early photographic process in which no negative was produced.
D. The 1843 photograph differs from authenticated photographs of Lincoln from the time before he was President in that those photographs show a man with a sunburned face and wearing rough clothes.
E. There is no surviving documentary evidence from Lincoln’s letters or elsewhere that he sat for a photograph at any time before 1846.
文章翻译：1843年的一张照片有时被认为是美国第十六任总统亚伯拉罕·林肯（1809-1865）现存最早的肖像。照片显示的是一张没有分下巴的脸，而林肯是有分下巴的。然而，由于熟练的底片润色可以不经察觉地改变底片上的特征，例如底片制作的肖像中的分下巴，因此没有分下巴不能作为这个照片不是林肯的确定证据。首先仍然是找出文章的结论是什么，这里的结论是没有分下巴不能作为这个照片不是林肯的确定证据。其次找论据，这里的论据一共有两个:
1）有照相底片
2）可以重新处理，对这两个论据任意一个取反，C选项对2）进行取反，为争取答案。
用这种方法可以解决削弱题中一半以上的题目！