第一段首先致谢：I am grateful to be employed as 职位+时间。Thank you for your kind attention and I would appreciate the opportunity of having worked here.
第二段表明自己要辞职，列出原因，比如离家远想换到更近的位置;工作不适合自己等等。现在给大家一个例子：However, I regret having to resign from my position. The reason for changing my working plan is that I have expected the job to be interesting and challenging, which turns out to be the opposite. As a young man full of enthusiasm, I therefore decide to quit this job for something else.可以根据自己的具体情况给出自己的理由，切不可千篇一律。
第三段简单表明希望得到允许、歉意及祝福：I sincerely hope that you approve of my resignation. I am sorry for any inconvenience caused. Wish you and your company great success in the future.