作业帮情态动词加上完成时的意思?
来源：学生作业帮 编辑：作业帮 分类：英语作业 时间：2024/05/04 21:54:50
情态动词加上完成时的意思?
could not have done
must not have done
should not have done
would not have done
以及它们的用法?
could not have done
must not have done
should not have done
would not have done
以及它们的用法?
could+have+done（过去分词）表示本来可能做的事却没有做.
eg:You could have phone me.你本可以给我打电话.
must+have+done表示对过去发生事情的猜测.
eg：You must have heard the news.你一定已经听说了.
should+have+done表示过去应该做某事却没做,有后悔之意.
eg：I should told you.我应该告诉你的.
would+have+done表示与过去事实相反的情况,即虚拟语气.
eg:I would have done it if I were you.我如果是你,就会那样做.
eg:You could have phone me.你本可以给我打电话.
must+have+done表示对过去发生事情的猜测.
eg：You must have heard the news.你一定已经听说了.
should+have+done表示过去应该做某事却没做,有后悔之意.
eg：I should told you.我应该告诉你的.
would+have+done表示与过去事实相反的情况,即虚拟语气.
eg:I would have done it if I were you.我如果是你,就会那样做.