"banGOO!"

I spend a small part of each day teaching a group of seven 2-year-olds English as a third language. Their first language is Korean, but they don't really have a grasp on any language quite yet. We do ABC and 1-2-3, songs, games, breaking up fights... And I noticed that the kids love to interrupt class saying this word "banGOO!" in conjunction with forceful gestures. They get a real kick out of it. After a few weeks of curiosity, I asked an adult wtf they were saying...

FART in Korean!