regret

遗憾；抱歉；悲叹英释nnsadness that you feel about something, especially because you wish it had not happened

后悔；惋惜；哀悼英释vvto feel sorry about something you have done and wish you had not done it

1 regret doing,对做过的事表示遗憾、后悔

2 to express regret,表示遗憾

1 It is with great regret that I must decline your offer..很遗憾，我不得不谢绝你的好意。