[求助]og196

444.It is possible that Native Americans originally have migrated to the Western Hemisphere over a bridge of land that once existed between Siberia and Alaska.
(A) have migrated to the Western Hemisphere over a bridge of land that once existed
(B) were migrating to the Western Hemisphere over a bridge of land that existed once
(C) migrated over a bridge of land to the Western Hemisphere that once existed
(D) migrated to the Western Hemisphere over a bridge of land that once existed
(E) were migrating to the Western Hemisphere over a bridge of land existing once

想请教  若不探究句意   C的用法 migrated over a bridge of land to the Western Hemisphere 有错误吗

3Q 3Q

OG说，

existing once in E is imprecise.

什么叫imprecise？？我觉得根本就是错的呀？？？

内容已删除

同问！

且B的existed once是不是错的？？

Choice D, the best answer, correctly uses the past-tense verb forms migrated and existed to refer to actions completed in’ the past. Choices A, B, and E present incorrect verb forms for expressing simple past action, and existing once in E is imprecise. Although choice C manages the correct tense, it misplaces the sentence elements so as to suggest that the Western Hemisphere once existed between Siberia and Alaska.

上面是OG的解释,这里so as to是什么意思?

哪位NN回答一下上面我的问题啊.这段OG解释的so as to是什么意思啊?记得以前说so as to的用法不对啊.

是否是修饰歧异啊？A of B ＋existing.... 是否是因为分不清到底是修饰A（a bridge）呢，还是修饰B( land)呢？

请求nn确认。