When I ask people what they regret most about high school, they nearly all say the same thing: that they wasted so much time.
With regard to our appointment on February 27, I regret to inform you that I will not be able to keep it because my business trip schedule has been changed.
After six months in China, you will realize that you regret not accepting that pizza before you left.
To my regret, my father could not recover from his long illness.
We can come to look upon the deaths of our enemies with as much regret as we feel for those of our friends, namely, when we miss their existence as witnesses to our success.
I regret the delay in writing to you to thank you for your hospitality on my visit to your country.
To my regret there are many students who cheat.
However, as soon as I saw the situation at the train station I began to regret this decision.
To our regret, we were obliged to call off the game, which we had been looking forward to.
For many years, my sister bitterly regretted
I left school at 16, but I've had a great life and I have no regrets.
If someone let me down but then showed sincere regret, I'd forgive them.
"British Airways regret to announce the cancellation of flight BA205 to Madrid."
We regret to inform you that you have not been shortlisted / I regret to say that we are unable to deliver your package this week / We regret to announce that flight LO278 is delayed.