GRE阅读真题机经及答案解析系列：Passage 72-GRE阅读真题免费下载

市面上流传的GRE阅读机经真题有三百多篇，同时又存在多种版本的答案和解析，有些疑难题目让考生不知道听谁的，还有些版本的解析像是用谷歌翻译把同题目和选项翻译了一下。TD GRE教研组认为，GRE阅读的解析，可以讲得再清楚一点。 GRE不光有技巧，不光有快速解题法，GRE更加考察大家的逻辑硬实力，文字理解实打实的深度。良好的GRE备考应当在课堂上向老师学习快速解题法，取同取反逻辑的同时，课下扎扎实实的读懂每一句话。读懂，是一切技巧使用的前提。皮之不存，毛将焉附？有感于此，我们尝试用比较长的时间，原创一个解析，力求做到超详细，大白话，包你懂。之前为大家推送了Passage 1 - Passage 71的解析，今天继续为大家推出Passage 72（长阅读）解析，这篇阅读一共有3段，共4道题，TD版超详细「包你懂」系列对此篇文章进行了清楚地解析。

GRE阅读真题第72段

Roughly 250 million years ago, in the worst series of mass extinction in Earth’s history, almost all species of life simply vanished. The traditionally held view has been that these extinctions occurred gradually, as changing environmental conditions—global cooling, global warming, dropping sea levels, or some combination of such factors—made life increasingly difficult during the last stages of the Permian period (284-245 million years ago). As Permian life-forms declined, they reached a fatal threshold and species succumbed to mass extinction. Supporters of the traditionalist view note that species begin disappearing from the fossil record well before the end of the Permian period. Yet, while such a pattern could have resulted from a slowly rising extinction rate, some scientists argue that just because a species disappears from the fossil record doesn’t necessarily mean it became extinct at that point. Moreover, Paul Wignall and others have found sites where marine fossil deposits reached a peak of diversity at the very end of the Permian period. Thus, Wignall believes late-Permian marine life was thriving until it was decimated suddenly by some catastrophe. Some geoscientists think that this catastrophe involved a meteor striking the earth. Michael Rampino, for instance, claims that a giant meteor crashed into Gondwanaland (the southern portion of the supercontinent Pangea, which covered about 30 percent of the globe in Permian times), setting off intense volcanism. Airborne soot and dirt from the impact blanketed Earth, inhibiting photosynthesis and triggering mass extinction of species. This view is widely disputed by traditionalists, however. Grant Young, for example, holds that the gradual breakup of the Pangean supercontinent triggered widespread climatic change and glaciation, causing the Permian mass extinctions to occur over millions of years. Glaciation, Young claims, has occurred throughout Earth’s history, and there is evidence that it occurred toward the end of the Permian period. Yet Rampino and others question one of the traditionalists’ basic assumption: the periodic occurrence of glaciation throughout Earth’s history. Crucial evidence includes the rock deposits know as tillites. because they resemble the unstratified drift produced by modern glaciers, geologists have long considered tillites to be signposts of glaciation. When trying to determine whether particular sedimentary layers represent tillite deposits, geologists look for stones with faceted shapes, scratched surfaces, and other features that presumably resulted from glacial action. The problem with ascribing all tillites to glaciation, however, is that tillite deposits are widespread in Precambrian sediments. Yet temperatures during the Precambrian (3.8 billion to 540 million years ago) are thought to have been warmer than those in today’s nonglacial world. Thus, Rampino thinks that certain tillites were produced by meteor impacts, not glaciers. The first compelling evidence that meteor impacts might have produced tillites came from Moon rocks that showed the same features as earthly tillites. Since no one believes the Moon ever had glaciers, that leaves but one possible cause: impacts.

GRE阅读文章解析

第一段第一句： Roughly 250 million years ago, in the worst series of mass extinction in Earth’s history, almost all species of life simply vanished. 白话版讲解： 在差不多两亿五千万年以前，在地球历史上出现的最严重的一系列物种大灭绝中，几乎所有的生物就这么消失了。 第二句： The traditionally held view has been that these extinctions occurred gradually, as changing environmental conditions—global cooling, global warming, dropping sea levels, or some combination of such factors—made life increasingly difficult during the last stages of the Permian period (284-245 million years ago). 白话版讲解： 传统的观点认为，生物灭绝是逐渐、慢慢发生的（不是突然的一次性事件），因为环境的变化让生活在二叠纪时期最后阶段的生物越来越难以存活下来。这些环境的变化包括全球气候变冷、全球气温变暖、海平面降低，或者是这些因素综合起来所造成的环境变化。 第三句： As Permian life-forms declined, they reached a fatal threshold and species succumbed to mass extinction. 白话版讲解： 随着二叠纪时期的生物数量不断减少，这些生物数量减少到一个关键的阈值点。一旦生物数量低于这个阈值，物种就开始大规模的灭绝。第一段描述了历史上自然界发生的一次重大事件，并且对这次事件产生的原因给出了传统的看法。 第二段第一句： Supporters of the traditionalist view note that species begin disappearing from the fossil record well before the end of the Permian period. 白话版讲解： 这种传统观点的支持者注意到，在二叠纪时期结束之前，这些物种就从化石记录上消失了。（也就是说，这些人认为在二叠纪时期结束之前，这些物种就已经灭绝了。） 第二句： Yet, while such a pattern could have resulted from a slowly rising extinction rate, some scientists argue that just because a species disappears from the fossil record doesn’t necessarily mean it became extinct at that point. 白话版讲解： 但是，尽管这样的情况可能是由于逐渐升高的物种灭绝率导致的，也有科学家认为，这也有可能仅仅是因为某个物种在化石记录上消失了，并不一定就意味着这个物种在当时就已经灭绝了。 第三句： Moreover, Paul Wignall and others have found sites where marine fossil deposits reached a peak of diversity at the very end of the Permian period. 白话版讲解： 另外，Paul Wignall 和其他人发现海洋化石堆积的地方，其（化石的）多样性在在二叠纪时期结束的时候达到了顶峰。 第四句： Thus, Wignall believes late-Permian marine life was thriving until it was decimated suddenly by some catastrophe. 白话版讲解： 因此，Wignall 认为，二叠纪时期晚期的海洋生物是非常繁荣的，直到因为某个重大自然灾难而突然地大规模毁灭了。这一段对二叠纪时期出现的大规模物种灭绝给出了新的解释。传统观点认为当时的物种是受到环境影响而逐渐灭绝的。但新的观点认为，这些物种是因为某件重大自然灾难在突然之间被摧毁的。 第三段第一句： Some geoscientists think that this catastrophe involved a meteor striking the earth. 白话版讲解： 一些地学科学家认为，这样的一次重大自然灾难和流星对地球的撞击有关。 第二句： Michael Rampino, for instance, claims that a giant meteor crashed into Gondwanaland (the southern portion of the supercontinent Pangea, which covered about 30 percent of the globe in Permian times), setting off intense volcanism. 白话版讲解： 比如，Michael Rampino 就认为，一个大型的流星撞到了冈瓦纳大陆（Gondwanaland）上。冈瓦纳大陆是一个超大陆——泛大陆（Pangea）的南部。在二叠纪时期，泛大陆覆盖了地球 30% 的面积。这次撞击造成了剧烈的地震。（注：泛大陆是指在古生代至中生代期间存在的大片陆地。） 第三句： Airborne soot and dirt from the impact blanketed Earth, inhibiting photosynthesis and triggering mass extinction of species. 白话版讲解： 撞击产生的烟尘和泥土在空气中传播，将地球覆盖了起来。这阻碍了光合作用的发生，导致了物种的大规模灭绝。这三句话描述了新观点持有者的看法，认为是流星撞击地球这件事导致了物种突然之间大规模灭绝。 第四句： This view is widely disputed by traditionalists, however. 白话版讲解： 但是，这种观点遭到了很多传统观点持有者的反对。 第五句： Grant Young, for example, holds that the gradual breakup of the Pangean supercontinent triggered widespread climatic change and glaciation, causing the Permian mass extinctions to occur over millions of years. 白话版讲解： 比如，Grant Young 就认为，泛大陆的分裂引发了大规模的气候变化和冰川时期出现，从而导致了二叠纪时期的大规模生物灭绝持续了百万年、上千万年的时间。 第六句： Glaciation, Young claims, has occurred throughout Earth’s history, and there is evidence that it occurred toward the end of the Permian period. 白话版讲解： Young 认为，冰河时期在地球的发展过程中出现过多次，而且有证据表明在二叠纪时期的末期也出现了冰河时期。这三句话（第四——第六句话）总结了传统观点支持者对于新观点的反驳。传统观点持有者认为是地球发展历史过程中出现的若干次冰河时期导致了生物灭绝，而且这个生物灭绝过程是比较缓慢的。 第七句： Yet Rampino and others question one of the traditionalists’ basic assumption: the periodic occurrence of glaciation throughout Earth’s history. 白话版讲解： 但是 Rampino 和其他人质疑了传统观点持有者的一个基本假设：也就是在地球的发展过程中，冰河时期定期地出现过若干次。（新观点持有者对传统观点持有者的这个假设进行了反驳，认为这个假设是不对的。） 第八句： Crucial evidence includes the rock deposits know as tillites. 白话版讲解： 关键性的证据包括冰碛岩这种岩石沉积物。 第九句： Because they resemble the unstratified drift produced by modern glaciers, geologists have long considered tillites to be signposts of glaciation. 白话版讲解： 因为冰碛岩和现代冰川产生的不成层冰碛物外形相似，所以地质学家长期以来都把冰碛岩看成是冰河作用的标志。 第十句： When trying to determine whether particular sedimentary layers represent tillite deposits, geologists look for stones with faceted shapes, scratched surfaces, and other features that presumably resulted from glacial action. 白话版讲解： 当地质学家尝试着去判断某个沉积层是否是冰碛岩的沉积物的时候，他们会去寻找带有某些特征的岩石。这种岩石具有的特征包括有多个面，表面有划痕，以及其它一些因为冰川作用而形成的特征。 第十一句： The problem with ascribing all tillites to glaciation, however, is that tillite deposits are widespread in Precambrian sediments. 白话版讲解： 但是，认为冰碛岩是冰河时期的产物这个观点有一个问题，那就是冰碛岩的沉积物在前寒武纪时期的沉积物中也是广泛存在的。 第十二句： Yet temperatures during the Precambrian (3.8 billion to 540 million years ago) are thought to have been warmer than those in today’s nonglacial world. 白话版讲解： 但是，一般认为，前寒武纪时期（36 亿年前到五千四百万年前）的气温比现在要更高（现在已经没有冰河时期了）。 第十三句： Thus, Rampino thinks that certain tillites were produced by meteor impacts, not glaciers. 白话版讲解： 因此，Rampino 认为，某些冰碛岩是流星撞击地球的产物，而不是冰川的产物。从第七句——第十三句，新观点持有者对传统观点持有者进行了反驳。新观点持有者认为，传统观点——冰碛岩是冰川的产物——是站不住脚的，并且引用了证据来对这个观点进行反驳。 第十四句： The first compelling evidence that meteor impacts might have produced tillites came from Moon rocks that showed the same features as earthly tillites. 白话版讲解： 第一个表明流星撞击地球产生了冰碛岩的有力证据来自于月球上的岩石，这些岩石具有和早期地球上的冰碛岩相同的特征。 第十五句： Since no one believes the Moon ever had glaciers, that leaves but one possible cause: impacts. 白话版讲解： 因为月球上有出现过冰川，所以只留下一种可能性：撞击。整篇文章围绕是什么导致了二叠纪时期出现生物大灭绝展开。文章第一段阐述了传统观点。传统观点认为是冰川作用导致了这次的生物大灭绝，而且这次的灭绝是一个缓慢的过程。文章第二段阐述了新观点。新观点对旧观点进行了反驳，认为流星撞击地球导致了这次的生物大灭绝，而且这次的灭绝是一个突然的过程。文章最后一段给出了新观点对旧观点进行反驳的相关证据。

GRE阅读题目解析

1. The primary purpose of the passage is to A. consider new applications for a traditional methodology. B. present a challenge to an established idea. C. question the purported severity of a particular phenomenon. D. discuss the implications of a controversial position. E. identify similarities underlying two contrasting arguments.

白话版讲解： 第一题：文章的主旨大意是什么？这道题的正确答案是 B。根据对文章结构的分析可以判断出，整篇文章是在对某个自然现象传统解释进行了反驳，并且阐述了相关证据。 A. 考虑对于一种传统的方法进行新的应用。 B. 对一个已经被认可的观点提出质疑。 C. 质疑了某个现象的严重性。 D. 讨论了某个具有争议性的观点所暗含的意义。 E. 识别出了两个相对立的观点之间的相似之处。 2. According to the passage, the claim that all terrestrial tillites resulted from glacial action is undermined by the A. surface features of most terrestrial tillites. B. resemblance that exists between terrestrial tillites and unstratified drift. C. number of terrestrial tillites that date from the Precambrian period. D. facts that most terrestrial tillites are found in sedimentary deposits. E. evidence that they resemble the drift produced by modern glaciers.

白话版讲解： 第二题：根据文章内容，认为所有陆地上出现的冰碛岩都来自于冰河作用的这个观点会被哪个选项的内容削弱？这道题的正确答案是 C。题目对应的原文内容出现在文章第三段的第十一、十二句。（The problem with ascribing all tillites to glaciation, however, is that tillite deposits are widespread in Precambrian sediments. Yet temperatures during the Precambrian (3.8 billion to 540 million years ago) are thought to have been warmer than those in today’s nonglacial world. ） A. 大部分陆地冰碛岩所具有的外表特征。 B. 陆地冰碛岩和不成层的冰碛物外形相似。 C. 从前寒武纪时期存在至今的陆地冰碛岩的数量。 D. 大部分的陆地冰碛岩都可以在沉积物中找到。 E. 证据表明这些冰碛岩和现代冰川产生的不成层冰碛物外表相似。 3. It can be inferred from the passage that author would agree that the similarity between terrestrial tillites and certain Moon rocks is significant because this similarity A. suggest that it is unlikely that glaciers have produced tillites on Earth. B. suggest that the rate of meteor impacts on the Moon is much higher than previously thought. C. provides the first compelling evidence that the Moon has experienced meteor impacts. D. supports Rampino’s explanation regarding the origin of certain terrestrial tillits. E. supports Young’s claim, regarding the periodic occurrence of glaciers throughout Earth’s history.

白话版讲解： 第三题：根据文章内容可以推断出，作者认为，陆地冰碛岩和月球上的一些岩石具有相似之处，这一点很重要，因为这种相似性怎么样？这道题的正确答案是 D。题目对应的原文内容出现在文章第三段的第十四、十五句。（The first compelling evidence that meteor impacts might have produced tillites came from Moon rocks that showed the same features as earthly tillites. Since no one believes the Moon ever had glaciers, that leaves but one possible cause: impacts.） A. 因为它表明了冰川作用不太可能会导致地球上的陆地冰碛岩的出现。 B. 因为它表明了流星撞击月球的速度比之前人们认为的更快。 C. 因为它提供了第一个证据，表明月球是遭受了来自流星的撞击的。 D. 因为它支持了 Rampino 关于某种陆地冰碛岩的起源的解释。 E. 因为它支持了 Young 的观点。他的观点和地球发展过程中，周期性的出现了冰河时期有关。 4.The passage suggests that the supporters of the traditional view would be most likely to disagree with the “scientists” (highlighted) over which of the following regarding the fossil record during the Permian period? A. the number of species that disappeared from the fossil record during the Permian period. B. the significance of a species disappearance from the fossil record during the Permian period. C. the point in time at which species began disappearing from the fossil record during the Permian period. D. the likelihood that the fossil record during the Permian period will be supplemented by new fossil discoveries. E. the likelihood that the fossil record during the Permian period is as accurate as the fossil records of other periods.

白话版讲解： 第四题：文章认为，支持传统观点的人和原文高亮出来的 “scientist”，在以下哪一个关于二叠纪时期的化石记录的说法上会产生分歧？这道题的正确答案是 B。题目对应的原文内容在第二段的第一、第二句。（Supporters of the traditionalist view note that species begin disappearing from the fossil record well before the end of the Permian period. Yet, while such a pattern could have resulted from a slowly rising extinction rate, some scientists argue that just because a species disappears from the fossil record doesn’t necessarily mean it became extinct at that point. ）旧观点认为二叠纪时期结束之前，这些物种就从化石记录上消失了，意味着物种在那个时候就已经消失了。但是新观点认为，仅仅是因为某个物种在化石记录上消失了，并不一定就意味着这个物种在当时就已经灭绝了。所以两者是在化石记录的重要性上产生了分歧（一个认为意义重大，一个认为意义没有那么重大。） A. 在二叠纪时期，从化石记录上消失的物种数量。 B. 在二叠纪时期，从化石记录上消失的物种的重要性。 C. 在二叠纪时期，物种从化石记录上消失的具体时间。 D. 新发现的化石可以补充二叠纪时期的化石记录的可能性。 E. 二叠纪时期的化石记录和其它时期的化石记录一样准确的可能性。