情态动词can't have done 和couldn't have done 有什么区别吗
对过去发生的事情否定猜测用can't have done 或couldn't have done ,两者有区别吗?
比如 He can’t have gone to Beijing for I saw him a minute ago. 能换成He couldn’t have gone to Beijing for I saw him a minute ago.吗?
谢谢