从新prep1 188想到的

制约与平衡

188.(26379-!-item-!-188;#058&001961)



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 the brain 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,

这也也是一道旧prep的题
正确答案是A，做错过的时候选的是E
我认为A中的having是省略了主语的状语。该句可以使Having……，N are……
因为having……其实就是省略了相同的主语和从句引导词的状语从句。还原后是After N have ……，N are……

对于E选项来说drawing是伴随状语。但是伴随状语要求两个状态或是动作同时发生。很明显这两个动作不能动时发生。（估计想伴随have done是不是都要用having done）

请问各位牛人这样的思路是否正确？

bdsjb116

顺带问一句: 伴随状语之前是否能加修饰成分，如lz题目中的E中的now是不是不应该加?

Neuroscientists have amassed a wealth of knowledge, (now) drawing solid...

sarahLS

鄙人认为这道题 之所以不选E是因为  E改变了原句的合理重心。
原句的having ...knowledge  这个是作为定语来修饰... scientists 的，而原句的主干就是scientists draw solid conclusion to sth.

而E选项使得各成分的关系颠倒了。。。。
不知道这样解释清不清楚？

还有我认为在伴随状语前加上 now ,currently  这些词应该是没有关系的

但是GMAT语法题有个原则是不改变原句的合理重心及意思，所以这个要分情况的~！