Zip-Boing, A game of no teeth

Zip! Bong!: A game of no teeth!. Everyone must cover their teeth with their lips so we can’t see them. In a circle, if the game is going to the left, if someone says zip, you continue passing the zip sound in the same direction, if they say bong, it is reversed. The game continues until someone makes a mistake, or smiles so that their teeth are showing. Then that person is out, and the circle is made smaller.