The purpose of this letter is to invite you and your organization,. , as a public service, to our (name of career fair expo) from ____________a.m.Write an invitation letter, in English, inviting the individual for a visit. Provide evidence of your valid student status with and a photocopy of your: To register with Bexar County, verify your eligibility. This is a sample letter of invitation for inviting parents to the United States of America. This sample is used for illustrative purposes only.