【答案解析】
Dear Prof. Smith,
I"m writing to express my sincere thanks to you for the clear guidance and patient instruction I received during my study at the Teachers" College.
The study provided me with an opportunity to get some fresh ideas on Canadian literature which would be of great help to my teaching in China. I enjoyed discussing with you on cultural differences between the East and the West and I felt greatly enlightened by your wonderful remarks.
I"m afraid, that my poor comprehension of some original Canadian literature must have given you a great deal of trouble, but I know you will forgive me for my naive ideas.
Please give my best regards to your family and accept the same yourself.