Dear {Recipient} , I would like to apologize to you for {behavior}. I did not know that {behavior} is considered inappropriate in your culture. In my culture, {behavior} is considered acceptable and is in fact quite common. Now I know that in your culture, {behavior} means {explanation}. I am very sorry to have offended you. I have now educated myself further about your culture, and I hope that this incident will not affect our future relationship. Sincerely, {Sender}