would和should的用法,虚拟语气中有什么区别?以括号中所给词的适当形式填空：The petrol tank is empty.I ______(fill) it up before we left home.答案是should have filled请问1、这道题是虚拟语气吗?2、为什么不能用“would have filled”?关于这个问题的第2个例题：Had electronic computers not being invented,many problems of space flight _____ now.(A) would not have been solved(B) would not be solved(C) must not be solved(D) should not have been solved麻烦请问B、C、D为什么不对？
问题描述：
would和should的用法,虚拟语气中有什么区别?
以括号中所给词的适当形式填空：
The petrol tank is empty.I ______(fill) it up before we left home.
答案是should have filled
请问1、这道题是虚拟语气吗?
2、为什么不能用“would have filled”?
关于这个问题的第2个例题：
Had electronic computers not being invented,many problems of space flight _____ now.
(A) would not have been solved
(B) would not be solved
(C) must not be solved
(D) should not have been solved
麻烦请问B、C、D为什么不对？
答
1.是虚拟语气。用should可能是要表达“应该”之意，用would则只表达“将”。
2.第二题的B,C肯定排除。剩下的解释遵循1。呵呵
答
不是虚拟语气....
should have done表示应该做的事没做,通常叫做“情态动词表推测”。
答
should have done 是翻译为本该做某事 而没做 would have filled 没有这个意思1 Like the rules governing the use of shall and will on which they are based, the traditional rules governing the use of should...