GRE阅读真题之OG整合

第 1 页精品文档---下载后可任意编辑GRE 阅读真题之 OG 整合 想要提高 GRE 阅读成果，就一起来看看 GRE 阅读真题之 OG 吧，下面我就和大家共享，来观赏一下吧。 GRE 阅读真题之 OG OG-1 Passage 15 At a certain period in Earth’s history, its atmosphere contained almost no oxygen, although plants were producing vast quantities of oxygen. As a way of reconciling these two facts, scientists have hypothesized that nearly all of the oxygen being produced was taken up by iron on Earth’s surface. Clearly, however, this explanation is inadequate. New studies show that the amount of iron on Earth’s surface was not sufficient to absorb anywhere near as much oxygen as was being produced. Therefore, something in addition to the iron on Earth’s surface must have absorbed much of the oxygen produced by plant life. 第 2 页精品文档---下载后可任意编辑 1. In the argument given, the two portions in boldface play which of the following roles? A. The first is a claim made by the argument in support of a certain position; the second is that position. B. The first is a judgment made by the argument about a certain explanation; the second is that explanation. C. The first expresses the argument’s dismissal of an objection to the position it seeks to establish; the second is that position. D. The first sums up the argument’s position with regard to a certain hypothesis; the second provides grounds for that position. E. The first is a concession by the argument that its initial formulation of the position it seeks to establish requires modification; the second presents that position in a modified form. GRE 阅读真题之 OG 第 3 页精品文档---下载后可任意编辑 OG-1 Passage 16 Animal signals, such as the complex songs of birds, tend to ...