雅思阅读长难句100句及翻译(3)_雅思英语阅读

雅思阅读长难句100句及翻译(3)

　　49. Most striking among the many asymmetries evident in an adult flatfish is eye placement： before maturity one eye migrates，so that in an adult flatfish both eyes are on the same side of the head. 在一条成年比目鱼身上显著存在的诸多不对称（asymmetry）特征中，最为吸人注目的是眼睛的摆位：在成年之前，一只眼睛发生移动，因此在成年比目鱼身上，两只眼睛均位于头部的同一侧面。

　　50. A critique of Handlins interpretation of why legal slavery did not appear until the 1660s suggests that assumptions about the relation between slavery and racial prejudice should be reexamined , and that explanations for the different treatment of Black slaves in North and South America should be expanded . 一个对于H的关于为何法律上的奴隶制没有在17世纪60年代以前出现的原因所作解释的批评显示，关于奴隶制和种族偏见之间的关系的假说应当重新检查，而且显示出，对于在北美和南美之间的对黑怒的不同处理的解释应当被扩展。

　　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。