Regret: regret to do sth.

对马上要做的事表示遗憾；

I have no regret to do like this.

我毫不后悔这样做了.

Love meaning to begin regret to need

（只为记忆方便, 不求精确）: 爱情意谓开始所需的悔恨

I regret to hear of your sister's death.

我为你妹妹的死而感到悲哀。

Regret to say that we are unable to help you.

很遗憾，我们不能帮助你。

Regret to tell you that you failed the test.

我遗憾的告诉你你没有通过考试。

We regret to say that your price is too high.

非常遗憾,你方的报价实在太高.

We regret to say our offer has lapsed unaccepted.

很遗憾,我们的报盘在失效前未被接受.

Avoid: Regret to loiter, bewilder to busy unpromising.

自我避免: 因虚度年华而悔恨, 因碌碌无为而迷茫!

Regret to inform you that your account is over drawn.

我们遗憾地通知你，你的账户已经透支了。