You can get the sample format from below link:
http://www.immigrationboards.com/viewtopic.php?t=15879
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Letter format for English Language Requirement
TO WHOM IT MAY CONCERN
This is to certify that Mr. XXXXX was a student of the XXXXX University in Bachelor of Commerce degree program from the year 1996 to1999.
He was awarded Bachelor of Commerce degree in the First Class division in the year April 1999 under Regd. No: XXXXX.
This is also to certify that Bachelor of Commerce is a degree program with the medium of instruction in English. Consequently all the three years were taught in English Language.
Registrar
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