第1个回答 2011-10-12
上句可转换为条件状语从句与过去相反的虚拟语气:If it had been in ancient times , our ancesters would have taken days to reach the places which we can travel to in an hour. 就好理解了。本回答被提问者采纳
第2个回答 2011-10-12
would have taken 与过去事实相反的虚拟假设,意为:本来会花去(我们祖先好几天时间才能到达)
第3个回答 2011-10-12
在这里是虚拟语气,表假设,因为不是现实发生的事所以用would have taken