【答案解析】Dear Mr.Wang,
I"m leaving for home tomorrow. I feel I can"t leave China without writing to thank you for your help during my tour in Chongqing. Chongqing has been greatly developed and changed in recent years, which has left me a deep impression. I am looking forward to another visit here and extending my warm welcome to your visiting New York.
All the very best for you and thank you again for your hospitality.