Dear Boss
I am writing to inform you that due to some family reasons, and followed by serious consideration, I would like to hand up my resign letter here.
I treasure my experience in Sales & Marketing Department, especially in xxx project team and I'll never forget my partners, supervisor and anther team members, who gave me care, friendship and support generously and continuously. I do wish Sales marketing department and my beloved team could have a more splendid future.
Thank you for your continued confidence in me throughout the past one year.
Sincerely Yours