Mind your manners BY DAVE BARRY (This classic DAVE BARRY column was originally published Nov. 24, 1996.) Today's etiquette topic is: Proper Table (burp) Manners. I have here a letter from Jean Gerdes, who teaches Family and Consumer Science to 6th-graders at the Donegal Middle School in Marietta, Pa. She states: ''I would like to ask your help in teaching my students the importance of good manners. I have found that if they can see how good manners might help them in their future, they are more motivated to learn and practice them. It would be a great help if...