How to email Graduate Director that I will not attend (F1 student) I have made some wrong decisions during my PhD studies in a US university (let's call it University X). One year ago, I got another admit(let consider this University Y)  when I got admit to University X. I didn't have fund to join university Y, thats why I got accepted the offer from university X. 

Now university Y offered me admission plus funds  and I accepted it, even the admission procedure has been completed. I have not transferred my sevis  no yet. 

After a lot of thinking I have decided that I will not transfer to another university, rather I will complete my PhD here. 

How can I email to the graduate director of University Y that I want to cancel my admission there and I do not want to join their program?
Agree - you have to tell Y. I agree with the above but add capitals to Admissions Committed.

Dear Professor X

Thank you very much for the offer of funding to complete my PhD with [name of uni]/your Faculty/Department [match to the Director's level of appointment].    After some thought, I have decided, respectfully, not to accept the offer.

I remain though very grateful for your consideration and I would like, through you, to convey my thanks to the Admissions Committee for their support.

With kind regards,
Sincerely,
ZZ