Dear Mr. Darwin:
I apreciate your kindness in sparing your valuable time for me during my recent visit to Ottawa. It was indeed a rewarding and enjoyable meeting. I hope our cooperation in Canadian market will bring about the desired results.
Again, thank you for the hospitality. I look forward to meeting you soon.
Very sincerely your,这是一篇感谢信，你稍微改动一下就可以了。