When you hold in a fart, it won’t always stay in your body. It finds another way to get out. First, it goes back to your intestines (肠). Later, it goes to the liver (肝脏). The liver makes it clean. Then, it keeps moving and goes to your stomach and lungs. At last, it comes out of your mouth. Ew, that sounds disgusting. Next time, you’d better not hold in a fart.