-You must cover your mouth before your sneeze, cough, yawn or burp. This is because of all the germs in the mouth. It is best to cover your mouth with a clean tissue, especially for a sneeze, but if you don’t have a tissue, at least cover your mouth with your hand. If you don’t cover your mouth, your friends might be angry that you put so many germs into the air. After sneezing, coughing, yawning or burping, it is good manners to say “Excuse me”