couldn't have done?couldn't have done究竟表示对过去的否定推测,还是表示本不能做到的事做到了?

分类: 作业答案 • 2021-12-18 17:08:59

问题描述：

couldn't have done?
couldn't have done究竟表示对过去的否定推测,还是表示本不能做到的事做到了?

答

could (不能用 can) have done 表示“过去本能够做某事却未做.”注意：其否定形式 couldn't have done 没有虚拟语气的用法,couldn't have done 只能表推测,相当于 can't have done,意为：“过去不可能做了某事.”