看了n遍也没看懂的一道og语法题

richygogogo

Neuroscientists,having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, are now drawing solid conclusions about how the human brain grows and how babies acquire language.
(A) Neuroscientists, having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, are
(B) Neuroscientists, having amassed a wealth of knowledge about the brain and its development from birth to adulthood over the past twenty years, and are
(C) Neuroscientists amassing a wealth of knowledge about the brain and its development from birth to adulthood over the past twenty years, and are
(D) Neuroscientists have amassed a wealth of knowledge over the past twenty years about thebrain and its development from birth to adulthood,
(E) Neuroscientists have amassed, over the past twenty years, a wealth of knowledge about the brain and its development from birth to adulthood,
想问一下D,E哪里错了？大神们指点一二！

Fiona09

版上曾经有人讨论过介个问题，也有人专门总结过。po链接，供LZ参考~~

http://forum.chasedream.com/foru ... &fromuid=809886

Nievesma

我从句意考虑，这句话的intending meaning是想说 neuroscientist 现在 are drawing·····。这个现在的状态是作者想要表达的重点，而having 这块是介绍说在这之前这么多年神经学家已经收集很多了知识，用，ing形式做插入语，这部分不是作者想要说的重点，因为强调的是现在可以draw solid conclusion了。D和E语法上的错误我没细看，但是它们把have 部分作为主要陈述内容而把现在的部分做成状语了，就改变了原来句子的意思，所以就排除了。希望有帮助~

richygogogo

我想问一下在第一遍做题的时候肯定不知道题目到底在强调哪一项，对吧？那怎么知道到底是在强调“收集知识”，还是在强调“现在做出结论”呢？而且有很多时候og说有的选项违背了原句想要表达的重点，比如把修饰成分作为了句子内部成分，但是有时候原句不一定正确，所以把原句的修饰成分作为句子内部成分一定错吗？