——How dare you talk to your teacher like that?——Well,now i regret ever (having done) that.

问题描述:

——How dare you talk to your teacher like that?——Well,now i regret ever (having done) that.
为什么要用having done

首先表示后悔做某事,用regret doing sth其次表示已经做了这件事,用完成时态,所以答案就是having done.翻译过来就是,我后悔做了这件事.