pia - beer
Kaua e kai pia ngaungau ki te kura.Don't chew gum at school.Negative active commands - Don't! - Kaua e..., kāti...
Kua inu pia koe?Have you been drinking beer?Gerund phrases (fence building, bread baking, dishes washing...) - tunu parāoa...
Kāore e āhei te inu pia, te kai paipa rānei, i konei.Drinking or smoking is not allowed here.Allowed to do something - āhei