3rd November 200X
Dearxxx
I regret to inform you that I decided to resign from my present position as (position) with effective from (next day of last date).
Thank you for giving me a chance to learn and to gain the valuable experience in (company name and section work with). I hope my resignation would not cause you much inconvenience.
Thank you for your kind attention and would appreciate if you could let me have a reference letter before I leave.
Yours faithfully,
(your full name)
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