1.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办公室在Lille国际博览会上提供的服务提交了帐单。一个月过去了你既没有付款也没有认可帐单。请检查这一疏忽并在最方便的时候付款。期望以后还为你公司服务。 
  
谢谢您能对此事尽快重视起来。