regret to do 對要做的事遺憾。 (未做)

　　regret doing 對做過的事遺憾、后悔。 (已做)

　　I regret to have to do this, but I have no choice.

　　我很遺憾必須這樣去做，我實在沒有辦法。

　　I dont regret telling her what I thought.

　　我不為告訴她我的想法而后悔。

　　典型例題

　　---You were brave enough to raise objections at the meeting.

　　---Well, now I regret ___ that.

　　A. to do B. to be doing C. to have done D. having done

　　答案：D。regret having done sth. 對已發生的事感到遺憾。regret to do sth. 對將要做的事感到遺憾。本題為對已說的話感到后悔，因此選D。

　　remember doing/to do

　　remember to do 記得去做某事 (未做)

　　remember doing 記得做過某事 (已做)

　　Remember to go to the post office after school.

　　記著放學后去趟郵局。

　　Dont you remember seeing the man before?

　　你不記得以前見過那個人嗎?

　　stop doing/to do

　　stop to do 停止，中斷做某事后去做另一件事。

　　stop doing 停止做某事。

　　They stop to smoke a cigarette. 他們停下來，抽了根煙。

　　I must stop smoking. 我必須戒煙了。

　　典型例題

　　She reached the top of the hill and stopped ___ on a big rock by the side of the path.

　　A. to have rested B. resting C. to rest D. rest

　　答案：C。由題意可知，她到了山頂，停下來在一個路邊的大石頭上休息。因此，應選擇"stop to do sth. 停下來去做另一件事"。而不僅僅是爬山動作的終止，所以stop doing sth.不正確。