1. that sex ratio will be favored which maximizes the number of　descendants an individual will have and　hence the number of gene copies　transmitted. (难度系数5,下同)

译文：那种性别比例能在最大程度上增加一个个体所能拥有的后代数量,并因此能在最大程度上增加所传递到后代身上去的基因复制品的数量。gre阅读难句训练方法倒装句的介绍!

a本句的正常语序应当是：that sex ratio which maximizes the number of descendnts an individuall will have and hence the number of gene copies transmited will be favored.但是因为主语that sex　ratio之后的以which引导的修饰它的定语从句,如果按照以上语序,则有头重脚轻之感。所以原文将此长长的从句倒装成谓语will be favored之后。

b在which引导的从句中,有两处省略：第一处在maximize的第一个宾语the number of descendants that an individuall will have中,　an individuall will have是修饰descendants的定语从句,但是,因为descendants在从句中作have的宾语,所以引导词that可以省略。第二处省略 是在第二个the number of 之前,省略了与前面一样的成分that sex ratio which maximizes. and hence在此表示后面的成分作为前面最大化一个个体的后代的数目的结果。

意群训练：that sex ratio will be favored which maximizes the number of　descendants an individual will have and　hence the number of gene copies　transmitted.gre阅读难句训练方法倒装句的介绍!