Search:

разрешите - Allow me (formal)
позвольте - Permit me (formal)

I wouldn't recommend using these during a game, unless it is against a grandmaster and you are kicking his behind :)

можно - mozhno - May I/ can I? Correct!

Нельзя - nelzya - means that it is not allowed, an illegal move

я не могу - ya ne mogu - I can not (go), I think is sufficient

also useful:

твоя...