结构推理 Writing letters according to the following requests.
【正确答案】Dear Sirs,
   With reference to your outstanding payment expiration last season, Enclosed please find our Debit Note 101-55 covering total amount US $10500.
   One month has passed since the goods were shipped, so we hope to receive all the outstanding payment before the end of this season.
   Please fax us when remitting.
【答案解析】