兹邀请由您领导的北京4人代表团来***(国家)参加***(展览)。该展览将于***(日期)在***(地点)举行。请您安排来***(国家)的必要事宜。展会期间您们将在此逗留***日，所有的费用，包括国际机票、当地交通、食宿、医疗保险和其他相关费用由贵公司承担。我们期待您的访问。
此致敬礼
(Salutation)
I would hereby invite the members of Beijing delegation totally 4 persons (listed attachment) led by you, to come over to ***(country) for *** (exposition), which is to be held at *** (place)during *** (date). Please make the necessary arrangements for your delegation to arrive in *** (country). During the exposition, you will stay here for *** days. All your expenses including international air tickets, local transportation, accommodations, medical insurances and all other related expenses during your stay here will be paid by yourselves. We are looking forward to greeting you in *** (country) very soon.
Yours sincerely, (Signature) 商务邀请函是正式公函，请用单位带英文抬头、地址、电话的信纸打印，结尾加盖公章。
美国签证商务邀请函