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.

请问为什么不是A？❓

请问此题为什么不是B而是E？

为什么不是C？

@May 老师，想请问一下GMAT考试数学部分，代数题目多吗？在整个31道题中，大概会占多少比例？考察点是有规律地按比例出现吗？有的话，几何、应用题等又分别占比多少？谢谢！

请唐塘老师解答下这道主旨题如何通过范围大小作答是?D和C比的时候比不出来. 其他几个可以说说思路吗 我对比下老师的思路和我排除的思路

金老师，有两个问题烦请帮忙解答。@金栩竹 1. 语法基础课，定语从句，例8，答案选C，主语是A pair of architects，谓语动词不是应该用单数形式嘛？ 2. 为什么说GMAT中不会出现which指代整句？

金栩竹老师，不好意思，因为我有几道题目想并在一起比较一下，所以还是通过截图来提问了hhh,第一道问过的这题，老师你说可以通过it无所指来去掉选项，但是it不是很明确地指代前面的43 percent嘛，老师你不是说代词只要看到有可以指代的就可以pass吗，还有compared with 后面是不是得紧跟要比较的对象，不能是a dacade ago，而且compared with a dacade ago是不是不能想成是省略一部分内容啊？就是类似于than以前后省略一部分，只留下状语这样。 第二题，比较对象是数字，所以不能用those指代人对嘛？ 第三题，为啥c不对啊？谢谢老师!

金栩竹老师，我想请教一下这个题目，能麻烦讲一下每个选项到底哪个和哪个在比，哪里错了嘛，我就是遇到xxx percentage of xxx，这种不知道怎么比较，到底对象是数字还是人

金栩竹老师，请问having done不能限制性修饰名词这是什么意思？E 选项不看别的错误点，只看having done 和were butchered不能平行，是因为时态不能平行:现在完成时和过去时不能平行还是因为主动与被动态不能平行呢？

请问唐塘老师这道题,由于我看的录播无法听到此作业题讲解时提问. 这道题你在讲的时候说用UG定位然后通过读文章发现并不是实验的结果然后再看上面一句. 我当时做题时直接用的是Theoretical economist的观点定位可以吗? 因为这和之前你讲的那个K`s objextion to M`theory差不多应该定位M的理论. 你要想undermine和object.那得和Theoretical economists说的内容沾边. 请问这样思考对吗?