Longman Dictionary of Contemporary English - regret

~1 v 1 to feel sorry about something you have done and wish you had not done it  (regret doing sth)  (She deeply regretted losing her temper.) + tha  (He regrets that he never went to college.) regret sth  (It's a great opportunity, Mr Jarvis - you'll never regret it. | bitterly/deeply regret (=regret something very much))  (It was a stupid decision and I bitterly regret it. | live to regret sth (=regret something later))  (I'm afraid this is a decision that he'll live to regret. | you'll regret it spoken (=used when threatening someone))  (You'd better not tell the police, or you'll regret it.) 2 (not in progressive) formal to be sorry and sad about a situation  (The management regrets any inconvenience caused to its customers. | I regret that formal (=used to politely say that you cannot do something))  (I regret that I will be unable to attend. | I regret to say/inform/tell (=used when you are going to give someone bad news))  (I regret to inform you that your contract will not be renewed.)  ( USAGE NOTE: REGRET GRAMMAR Regret is often followed by an ing form of a v, not often by the to form unless it is related to something that is about to be said. So if you say I regret to tell you this, but I just crashed the car, you mean I'm sorry, but I crashed the car. Compare this with I regret telling you I crashed the car. This means I'm sorry I told you I crashed the car. You regret something (NOT regret about/for something).