Mention how the experience has helped you grow professionally and personally. Thank your supervisor for their guidance and support throughout your internship.Below you'll find the best email template for accepting an internship – just fill in the blanks for yourself. Use this application acknowledgement email template to inform job candidates you received their application for one of your open roles. An internship completion letter is a formal acknowledgment that an intern has fulfilled the terms of their internship. You allowed me to see how a ____ business or shop works. I have learned new things and gained skills in ___.