请大家帮我解释下这几个英语句子Peopleweredifferentinthosedays.Howerehetreatedher,mygrandmotherwouldneverhaveleftmygrandfather.为什么要用wouldneverhaveleft这种形式啊Hereareyourorders:Youaretoreturnto

Question

请大家帮我解释下这几个英语句子
People were different in those days.Howere he treated her ,my grandmother would never have left my grandfather.为什么要用 would never have left 这种形式啊
Here are your orders:You are to return to Washington immediately.You are to return to 是什么结构啊

Answer 1

这两个问题都是时态
1,因为是虚拟语气,并且是对过去的情况的假设,所以用would have done,这个没有理由,需要背出来
意思是,那个时代很不同,无论爷爷怎么对奶奶,奶奶都不会离开他
2,这里是be + to do,一般将来时态,
表示即将发生的事情,有时候,还可以加be about to do
与别的一般将来时态还是有不同
is going to do打算,有计划的,或者专门用于天气方面
will do更强调一种意愿
举个例子
I am to be a teacher.我就要做老师了
I am going to be a teacher.我会做老师,无论什么过程,结果都是做老师
I will be a teacher.我想做老师