建议采用以下格式：
To Whom It May Concern.
Dear Sir,
This is to certify that Mr.Wang xx will,on behalf of the company,attend the Paris International Food Exhibition held in Paris during the period of October 17 through October 21,2010.Mr.Wang schedules to travel to France on October 15,2010 and stay till October 24,2010.
For any further inquiry,please feel free to contact me by:
Phone:
email:
Sincerely yours,
xxx
Title:
Company: