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 请问 D里的that是修饰 bridge还是修饰land? E中的land existing once怎么就imprecise? 我觉的D中的that修饰的是bridge. 因为A of B这类结构中中心词是A. E我觉得更不好的是时态吧。 |