[原创]求解prep语法新题一道prep1-188

zanyingsan

已经有两道题就是因为看见 having done 被我排除了，那个是平行，这个算啥？插入语？

xuxu2009

已经有两道题就是因为看见 having done 被我排除了，那个是平行，这个算啥？插入语？
可以这么认为

lxw19

但A的主语和BE动词之间隔得好远啊，感觉很别扭

cm_525

请问its指代什么？

avivazst

A用法很对的

tengjunshan

在讨论GMAT语法的时候曾经说过，完成时态的ing形式不能做定语，但是这里的having amassed做的是伴随状语修饰的后面的are drawing，这是可以的，也就是说申请科学家正在得出结论，而得出结论的过程的伴随过程是在过去的20年中积累了很多关于什么什么的财富。

AlohaDJ

re楼上tengjunshan的说法。

个人总结的关于having done的用法是：不可做先行词的后置定语，但可以做句子的状语。

waterlemonseed

顶having done，我记得白勇里面提到，看到having done就可以直接不用看了，唉

waterlemonseed

外国网站上找到的，我觉得很有道理


Perfect Participle:

The perfect participle indicates completed action. You form the perfect participle by putting the present participle having in front of the past participle.

For example:-

Having done, having finished, having read, having spoken

It can be used to form the passive voice.

For example:-

Having improved her English Pia's promotion prospects were much better.

Option E indicates that "having kept" is a completed action. So, it is not correct.

cptiger

主语Neuroscientists后面两个逗号间插入的部分，不管是状语还是定语，都可以看成是插入语，那么把句子稍微变化一下：
having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, Neuroscientists are now drawing solid conclusions about how the human brain grows and how babies acquire language.
是不是再看，就可以看出来是做状语的。Having done结构做定语有问题，但是做状语是OK的，请NN们拍砖！