类比题的概念

　　阅读文章中通常会给出一个原则或者情况进行对比分析，这种题通常采用相同原则，即举一反三。通常来说，它出现的方式是：以下哪个选项的描述与原文的叙述相似。碰到这种题的时候，不要贸然看选项，而要先注意题干的提炼，也就是原文的事例到底是怎样一种情况。掌握规律后，该类型题目也较为容易。它只是一种大致含义的相似，而不是精细的词义对仗。常见提问方式：…is most similar to which of the following? The author of the passage would be most likely to agree with which of the following statements about?

　　GMAT阅读类比题举例分析

　　Milankovirch proposed in the early twentieth century that the ice ages were caused by variations in the Earth’s orbit around the Sun. for some time this theory was considered untestable, largely because there was no sufficiently precise chronology of the ice ages with which the orbital variations could be matched.

　　To establish such a chronology it is necessary to determine the relative amounts of land ice that existed at various times in the Earth’s past. A recent discovery makes such a determination possible: relative land-ice volume for a given period can be deduced from the ratio of two oxygen isotopes, 16 and 18, found in ocean sediments. Almost all the oxygen in water is oxygen 16, but a few molecules out of every thousand incorporate the heavier isotope 18. When an ice age begins, the continental ice sheets grow, steadily reducing the amount of water evaporated from the ocean that will eventually return to it. (OG13阅读解析-14)

　　文章脉络

　　1. 文章第一段提出一种理论是无法证实的以及原因。

　　2. 文章第二段指出通过同位素O16和O18可以测试Milankovirch的理论

　　3. 文章第三段指出了这种方法的两个优点：一是全球性的记录;二是获得的记录具有连续性。

　　4. 文章第四段说明了还有其他一些原因会影响到气候，但是Milankovirch的理论可以得到证实。

　　1. The author of the passage would be most likely to agree with which of the following statements about the Milankovitch theory?

　　旨在考察我们对文章细节的认知。定位在第三段的最后一句。

　　选项分析：

　　(A) It is the only possible explanation for the ice ages. 这种理论是唯一一种可以解释冰河时代的，最后一段作者提出了还有其他方法，所以排除。

　　(B) It is too limited to provide a plausible explanation for the ice ages, despite recent research findings. 这种理论提供一个合适的解释具有局限性，作者是支持的并没有说到它的局限性，排除。

　　(C) It cannot be tested and confirmed until further research on volcanic activity is done. 这种理论不能被测试和证实，违背原意，排除。

　　(D) It is one plausible explanation, though not the only one, for the ice ages. 正确。这是一种合理的理论尽管不是唯一一种可以解释冰河时代的。定位在最后一段的内容。

　　(E) It is not a plausible explanation for the ice ages, although it has opened up promising possibilities for future research. 这种理论不合理，违背原意，排除。

　　答案：D

　　GMAT阅读类比题其实并不难，考生要做的就是了解类比题的特点，并掌握其常见的解题方法和技巧，然后加强练习。