Dear Mr. / Ms,
On 14 November I submitted a bill for services rendered to your office at the Lille International Exposition. More than a month has now elapsed without payment or acknowledgment of my bill. Please check this oversight,and remit payment at your earliest convenience. I look forward to future services to your corporation.
Thank you for your prompt attention to this matter.
Yours faithfully
尊敬的先生/小姐，
十一月十四日我向你辦公室在Lille國際博覽會上提供的`服務提交了帳單。一個月過去了你既沒有付款也沒有認可帳單。請檢查這一疏忽並在最方便的時候付款。期望以後還爲你公司服務。
謝謝您能對此事儘快重視起來。
你誠摯的