OG12-SC-21

yunshishow

21 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,
这道题选A，看来看去总觉得A选项里的having amassed不太对劲。难道不能直接用amassed修饰？什么情况下应该用having done这种形式修饰主语？

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好像说having done 是指过去做过的对现在有影响的事情， 如果直接用
amassing 的话 就有点现在正在 amass （积累）的意思了，amassed是绝对不能用的 欢迎指正！