| 1 | We are deeply regretful about this matter. | |
| 2 | He regrets not being able to come to the party. | |
| 3 | I'm quite sorry that I couldn't attend your wedding. | |
| 4 | We are very sorry to hear about the death of your father. | |
| 5 | I am very sorry that I can't come to your birthday party. |