两道PREP的题，关于介词短语修饰的问题。

b77p88

1010805556 发表于 2015-8-26 20:08
。。。。。第一题og的解释里根本没有修饰错误这么解释的。og中的解释的把 at acquiring carbon放后面可以消 ...

看一下！               

b77p88

1010805556 发表于 2015-8-26 20:08
。。。。。第一题og的解释里根本没有修饰错误这么解释的。og中的解释的把 at acquiring carbon放后面可以消 ...

看一下！               

b77p88

关于it they的完全指代，我还想再问一下……
160.(OG12-23)
In a previous design, the weight of the discus used in track competition is concentrated in a metal center, but now it is lined with lead around the perimeter, thereby improving stability in flight and resulting in longer throws.
A.        In a previous design, the weight of the discus used in track competition is concentrated in a metal center, but now it is
B.        According to a previous design, the weight of the discus used in track competition was concentrated in a metal center, but now it is
C.        Once designed with its weight concentrated in a metal center, the discus used in track competition is now
D.        The discus used in track competition, once designed with its weight concentrated in a metal center, but now         
E.        The discus used in track competition was once designed having its weight concentrated in a metal center and now
这道题中，OG的解释说A B选项中的it指代了weight 而不是指代weight of the d. 可是之前笔记里有说到，it they是完全指代，就是指代的对象包括和核心名词和它的修饰。
请问怎么理解？

还有，1010805556这位G友，实在不好意思，我不知道为什么每次我点回复都会自动变成 看一下！的字样…………