You borrowed an important textbook during the last term from a classmate. You now realize your classmate has returned home overseas and you still have the book.

I hope this letter finds you well despite the distance between us.

I am writing to sincerely apologize for the mistake I made in not returning the important textbook I borrowed from you last term. I realize now that you have returned home overseas, and I feel truly sorry for the inconvenience I have caused you.

I would like to inquire about the significance of the textbook to you. Could you please let me know how important it is and if there are any specific sections or notes in it that you need? Understanding its value to you will help me better address the situation.

Rest assured, I am committed to resolving this issue promptly. I will explore all possible options to return the textbook to you, whether it be through shipping it to your current address or finding someone who can deliver it to you personally. I will ensure that the book reaches you as soon as possible.

Once again, I apologize for the oversight and I appreciate your understanding and cooperation in resolving this matter. I look forward to hearing from you soon. Take care.