Dear Mr. Henderson,
I hope you are having a productive week. I am writing to sincerely apologise for failing to return the textbook I borrowed from you at the conclusion of our Business Communications course last month.
The book in question is 'Effective Professional Writing' by Dr. Alan Thorne. It has been sitting on my desk, and I am keen to get it back to you as soon as possible.
I found the chapters on persuasive report writing particularly insightful. The practical exercises significantly improved my ability to structure complex proposals, and I have already successfully applied these techniques in my current role at the marketing firm.
Unfortunately, I was unexpectedly sent on a two-week business trip to our regional office in Manchester just as the course ended. Between the heavy workload and the travel, the book completely slipped my mind until I returned home yesterday. I am truly sorry for this oversight and any inconvenience my delay has caused regarding your teaching materials.
I would be happy to drop the book off at the faculty office tomorrow morning if that is convenient for you. Please let me know if this works.
Best wishes,
Julian Thorne