给父母的邀请信格式(正式件)

Your question is not quite clear. What is this letter for?
Is it an invitation letter for your parents or your husband/wife,
or it's a petition letter to the officer to help your relative
get their visa (after being refused) ?
Anyway, following is the format of official invitation letter from
my university.

=================================================================

(Date)

To Whom It May Concern:
方鸿渐, currently a student at 克莱登 University, wishes to invite his mother, 方老太太, and his father, 方豚翁, to visit him in the United States. He would like his parents to arrive in May of
2000, and stay for approxiamtely three months.
We would appreciate any courtesy you may be able to extend to Mr. 方's parents so that they may be able to obtain visas to come to the United States to visit their son.
Thank you.

Sincerely,

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