Dear Ms. Baillie:
As of August 7, I will be terminating1 my employment at ABC Company. I have allowed two weeks prior to2 my departure for assisting in the transition process3.
Although I have enjoyed watching the Advertising Department grow from its humble beginnings4 to the current formidable5 size and influence in Wuhan, I have received an offer for another company that I feel is better suited6 to my career objectives.
I regret having to resign from my position. I wish you and ABC the best of luck and future success.
Sincerely,