在语法笔记中看到的内容:
97:Industrialization and modern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.这里面having可能修饰pollutants,也可能修饰they have introduced some 100,000 dangerous chemical pollutants整个分句,所以having产生了修饰歧义
但是,下面这道题的解释又让我觉得有些冲突:
188.
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,