Dear Matt,
I wish to thank you for all the help you have given me the past week. When my van broke down, I was really at a loss about how to transport the paper Denver to my store. Then you came along and offered to transport them for me. What can I say but thank you.
If you had not helped me, I would have to pay expensive charges to store the paper at the port. So please send me your bill for transporting the paper.
Yours sincerely,