I regret having left the work unfinished.这是什么语法现象?

I regret having left the work unfinished.这是什么语法现象? I regret having left the work unfinished ,I_everything ahead i regret having left the work unfinished,i should have plann He regretted that the work had been left unfinished. being　having是什么语法现象? i regret having missed the chance的问题 这句话是什么时态?I regret not having accepted your advice. Do you regret having left your first job why should I don't I'M having fun 这句子是什么语法啊? i feel left out 是什么语法结构 her work has been left unfinished since then 若错误应该怎样说 I have one day left 其中 left 是什么语法用法