Turhan kohtelias
Needlessly polite - and this is the most common place for an English speaker to end up, because every instinct you have is telling you to add something.
The imperative is the unlock. Ota, tule, istu, kysy - offers, all of them, and none an order. Once the command form stops sounding blunt, most of the rest arrives on its own.
From How Rude Is Your Finnish? - 6 lines of real spoken Finnish on Finnish IRL.