What do they mean?regret to do........regret doing.......后悔做了regret not to do...regret not doing...出處：P28I am dizzy a little.
熱心網友
一個是憒憾要做某事！比如：i am regret to tell you the sad news... 一個是后悔做了某事i am regret telling you the sad news...其它兩個就是否定意義！
熱心網友
regret to do......對將要發生（就是還沒發生，沒做的）的事表示抱歉、遺憾，和be sorry to do……相似reregret doing....對已經發生的事表示后悔，和be sorry have done相似下面兩個就是上面兩個的否定意思regret not to do...regret not doing...