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[Issue Essay]

试题详情

题目:

Analytical!

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答案:

提问:

老师您好能否帮我讲解下下面这个文章考试时该如何读,我读完这种文章压根不知道在说什么,只知道在讲ocean basin形成机制的几种理论。No very satisfactory account of the mechanism that caused the formation of the ocean basins has yet been given. The traditional view supposes that the upper mantle of the earth behaves as a liquid when it is subjected to small forces for long periods and that differences in temperature under oceans and continents are sufficient to produce convection in the mantle of the earth with rising convection currents under the mid-ocean ridges and sinking currents under the continents. Theoretically, this convection would carry the continental plates along as though they were on a conveyor belt (conveyor belt: n. 传送带) and would provide the forces needed to produce the split that occurs along the ridge. This view may be correct: it has the advantage that the currents are driven by temperature differences that themselves depend on the position of the continents. Such a back-coupling, in which the position of the moving plate has an impact on the forces that move it, could produce complicated and varying motions. On the other hand, the theory is implausible because convection does not normally occur along lines, and it certainly does not occur along lines broken by frequent offsets (an abrupt bend in an object by which one part is turned aside out of line) or changes in direction, as the ridge is. Also it is difficult to see how the theory applies to the plate between the Mid-Atlantic Ridge and the ridge in the Indian Ocean. This plate is growing on both sides, and since there is no intermediate trench, the two ridges must be moving apart. It would be odd if the rising convection currents kept exact pace with them. An alternative theory is that the sinking part of the plate, which is denser than the hotter surrounding mantle, pulls the rest of the plate after it. Again it is difficult to see how this applies to the ridge in the South Atlantic, where neither the African nor the American plate has a sinking part. Another possibility is that the sinking plate cools the neighboring mantle and produces convection currents that move the plates. This last theory is attractive because it gives some hope of explaining the enclosed seas, such as the Sea of Japan. These seas have a typical oceanic floor, except that the floor is overlaid by several kilometers of sediment. Their floors have probably been sinking for long periods. It seems possible that a sinking current of cooled mantle material on the upper side of the plate might be the cause of such deep basins. The enclosed seas are an important feature of the earth’s surface, and seriously require explanation because, in addition to the enclosed seas that are developing at present behind island arcs, there are a number of older ones of possibly similar origin, such as the Gulf of Mexico, the Black Sea, and perhaps the North Sea.

解答:

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阅读239323
解答: 郭培月

提问:

不知道自己判断标准是否对 前三相似,对比前三,按逻辑rules只能被intend,with intent、intending是主动,(实际做时,B我不知with intent是主动,我根据后面不是从句而是短语所以判断不如A);对比DE,D我觉得should不好,E的this指代不清。

解答:

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阅读231880
解答: 郭培月老师

提问:

DE读起来可以选对是E,但说不出为啥。

解答:

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阅读231449
解答: 郭培月老师

提问:

原文不长,读一下意思,看到than肯定要和前面并列形式一致,认为individuals是说某个物种,于是后面应该是别的物种。(按正确答案来,individuals应该是指基因的某几个组成部分???)

解答:

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阅读230053
解答: 郭培月老师

提问:

请问老师,这题选C???不是用答案带入直接选出B吗?17og的数学题,麻烦啦

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阅读229537
解答: 姜山老师

提问:


解答:

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阅读230023
解答: 徐小梅老师

提问:

请问这个第一句怎么翻译,what是引导的什么从句?

解答:

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阅读229737
解答: 金栩竹老师

提问:

Paleontologist Stephen Jay Gould has argued that many biological traits are not the products of natural selection, favored due to their enhancement of reproduction or survival, but that they are simply random by-products of other evolutionary developments. (A) due to their enhancement of reproduction or survival, but that they are (B) due to the reproduction or survival they enhance, but they are (C) because they enhance reproduction or survival, but (D) because they enhance reproduction or survival, but are (E) because of enhancing reproduction or survival, but are

解答:

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阅读229732
解答: 王文静老师

提问:

数学,余数问题如何求通项公式?

解答:

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阅读229269
解答: 姜山老师

提问:

for example、such as、include、contain、like的区别

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阅读229460
解答: 英吉老师

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阅读231307
解答: 金栩竹老师

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