Teacher! I am so sorry, I didn't prepare for the class.

　　老师!很抱歉，我没有做上课准备。

　　I’m so sorry.

　　很抱歉.

　　I’m terriblely sorry.

　　非常抱歉.

　　I’m terribly sorry about that.

　　为此我非常抱歉.

　　My apologies.

　　我道歉.

　　Please forgive me.

　　请原谅.

　　I hope you will excuse me.

　　希望您能原谅我.

　　It seems I owe you an apology.

　　我似乎还欠您个道歉。

　　Sorry about the inconvenience.

　　对不起添麻烦了.

　　It’s my fault. I really feel bad about it.

　　是我的错. 我真的感到很难过.