Invitation Letter Needed

Dear All Farangs Friends,

It's me again...hehe... this time i need some sample of "invitation letter" form. purpose of visit "Teaching"

because my bf rightnow being a teacher in University (part-time) and the university told him to find the format or template of this "invitation letter" , then the university can issue follow the format for him.

if somebody still keep the invitation letter. could you please scan or attach the file for me ? , you can delete your organisation and also your profile .. i just want the content inside the letter..

and another question is...

when the Tourist Visa (60+30) finished, can i use the "invitation letter" to change for the Non-B visa... at Immigration Bereau at BKK... without going outside Thailand ..? and can i use ONLY the invitation letter for the document to upgrade for non-B visa ?

thank you very much inadvance for your advise..

Regards,

Aae