雅思长难句一直是雅思阅读高分的拦路虎，新东方在线雅思频道为大家准备了100句雅思长难句，供大家学习。每天5句，由量变到质变，助大家攻克雅思长难句。本文是51-56句。

　　51. The best evidence for the layered-mantle thesis is the well-established fact that volcanic rocks found on oceanic islands，islands believed to result from mantle plumes arising from the lower mantle，are composed of material fundamentally different from that of the mid-ocean ridge system， whose source，most geologists contend，is the upper mantle.

　　对于地幔分层论点来说，最好的证据乃这样一个确认的事实，即在那些海洋岛屿——这些岛屿据信是源于由下层地幔升上来的地幔柱状溶岩流(mantle plume)——上发现的火山岩石，是由与海洋中部山脊系统的物质根本不同的物质构成的，而这一海洋中部山脊系统的成因，大多数地质学家论辩道，为上部地幔。

　　52. Some geologists，however，on the basis of observations concerning mantle xenoliths， argue that the mantle is not layered，but that heterogeneity is created by fluids rich in "incompatible elements" (elements tending toward liquid rather than solid state)percolating upward and transforming portions of the upper mantle irregularly，according to the vagaries of the fluids' pathways.

　　但是，某些地质学家，以对地幔捕虏岩体(xenolith)所作的观察为依据，指出地幔并非是分层排列的，相反，地幔的异质性是由那些富含"不相容成分"的流质构成的，这些成分趋向于流体而非固体的状态，自下而上渗透扩散，并依照这些流质流向的任意性，不规则地将上部地幔的某些部分予以改变。

　　53. Fallois proposed that Proust had tried to begin a novel in 1908, abandoned it for what was to be a long demonstration of Saint-Beuve's blindness to the real nature of great writing , found the essay giving rise to personal memories and fictional developments ,and allowed these to take over it a steadily developing novel.

　　F认为，P在1908年试图开始写一部小说，又为了写一部批判S-B的 伟大作品的真正本质的视而不见的长篇的证明而放弃了这部小说，其后又发现这一论文又勾起了其个人记忆及小说情节的萌生，使得后者取而代之形成了一部稳定展开的小说。

　　54. The very richness and complexity of the meaningful relationships that kept presenting and rearranging themselves on all levels，from abstract intelligence to profound dreamy feelings， made it difficult for Proust to set them out coherently.

　　各种有意义的联系在所有的层次上，自抽象的理性至深刻的梦幻般的情感，层出不穷并不断重新组合排列;正是这些有意义的联系的丰富性和复杂性，致使普鲁斯特难于将它们错落有致地安排好。

　　55. But those of who hoped, with Kolb, that Kolb's newly published complete edition of Proust's correspondence for 1909 would document the process in greater detail are disappointed.

　　但是我们当中的那些希望(也算上K本人)K新出版的P1909年书信的全集能够更加详细的记录下这一过程的人都大失所望。