In this email, I would like to thank you for your professional and effective guidance during my online learning in your college.
Your dedicated and passionate advice on all subjects were always a big help for me.
I have no words to express how grateful am that I have the Diploma completed and how much I enjoyed communicating with you.
Without your daunting efforts, I could never have made it in such time and with satisfactory quality.
Thank you once again for being an incredible teacher.