I'm really/so/extremely sorry.
我真的/非常/极其抱歉。
Please accept my/our/his/her apologies.
请接收我的/我们的/他的/她的道歉。
Please forgive me.
请原谅我。
I feel sorry terrible about this/my mistake/my behaviour.
我对我的错误/行为感到非常抱歉。
I want to apologize to you for what I've done.
我为我的所作所为向你道歉。
I owe you an apology.
我欠你一个道歉。
It was my mistake/all my fault.
这是都我的错。
My mistake/My bad.
我的错。
Dialogue1:
A: I'm so sorry.
很抱歉。
B: That's okay.
没关系。
Dialogue2:
A: I'm so sorry, I hope you can forgive me.
我很抱歉,我希望你能原谅我。
B: Well, I guess you didn't do it on purpose.
我猜你不是故意的。
Dialogue3:
A: Please accept my apologies.
请接受我的道歉。
B: Just this once. But please don't ever let it happen again.
就这一次,下次请不要再让这件事发生了。
Dialogue4:
A: I feel really sorry about this.
我对这件事感到很抱歉。
B: That's okay. But next time please try to be more careful.
没关系,但是下次请注意点。
Dialogue5:
A: My mistake, I'm sorry.
我的错,抱歉。
B: No problem. It could happen to anyone.
没关系,这种事会发生在任何人身上。