Dear Mr. / Ms,
Thank you for your letter conveying congratulations on my appointment. I wish also to thank you for the assistance you have given me in my work and look forward to better cooperation in the future.
Sincerely,
尊敬的先生/小姐，
感谢你来信对我的任命表达的祝贺。我也感谢您对我的工作给予的支持，并期望未来能有更好的合作。
诚挚的：