Dear ,
I am writing this letter to apologize that I will quit the position as …(职位) for the reason of myself.
During the span of working here, I was deeply impressed by the kindness, diligence of all staff members around me. But I have come to realize that the job probably is not suitable for me because…理由(兴趣爱好专业)。
So I am awfully sorry to tell you my decision to quit. Thank you very much for offering the opportunity to with an outstanding staff here. Please accept my apology.
Yours sincerely,
Li Ming