1. Sorry about that.
2. I'm terribly sorry.
3. I'm sorry to trouble you.
4. I'm sorry for troubling you.
5. I beg your pardon.
6. how was stupid of me.
7. I'm sorry I've kept you waiting.
8. I apologize.
9. Excuse me, may I speak to you for a moment?
10. Excuse me a moment.
11. I take the blame.
12. I honestly did not mean it.
13. I didn't mean in that way.
14. I throw myself upon your mercy.
15. I really don't know how to express how sorry I'm.
16. I've got to apologize for troubling you so much.
17. Please accept my apologies.
18. It's my fault.
19. How could I make it up to you?
20. How can you ever forgive me?
