Spot the Signs. Again, you may receive this response if you have specialized knowledge that would make it difficult or time_consuming to hire your replacement__or if it would be helpful for you to be actively involved in that search.
Basic of a Resignation Letter. There's no need to sugarcoat or get creative in the beginning; just state the position you're resigning from and the effective date. While you probably shared with your boss your reasons for leaving, you don't need to describe them here__keeping it simple is perfectly fine.