在数学中有一种概念叫做正态分布，意思是说在科学的测验或调查中，总是处在中间部分的个体数量最多，而在两端的个体数量较少。例如在参加雅思考试的考生中，得5分或6分的人数量最多，而考0分，1分和8分，9分的人数量很少。这是一个非常有用的原则，我们可以根据中间多，两边少的原则对题目进行分析，预测和猜答，十分有效。此法也可以进一步引申到几种被选答案的平均出现。下面仅举95年使馆样题的三道难度较大的题目进行分析。
18题到20题是一种难度较大的题型，考生首先要判断题干信息是否正确，如果正确，打勾；如果不正确，应把正确答案填在空白处。根据正态分布的规律，正确答案中必然会有打对勾的题目，所以如果考生只能够做出一道题目，不妨将剩下两个空全部填上对号；如果考生一道题目也做不出来，不妨将三个空全填对号，而答案中18题，20题答案为对号。这样考生至少就可以答对2/3的题目。
21题到24题，考生通过仔细观察题目会发现，Type of coffee这一横行应填I，R，或E。而这一横行中I和E两个选项都已经出现过了，所以如果考生没有做出21题和24题，可以猜答R，而正确答案21题和24题全部选R. 25题到32题，要求考生填1分，2分或3分，根据正态分布原则，考生对于没有听出来的题目，可以猜答2分，而正确答案中有5个是填2分。
上一篇： “烤鸭”必读：雅思听力训练之四遍精听法
下一篇： “烤鸭”必读：托福听力与雅思听力的区别
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