While eating (in Thai), we would need to have manners do not interfere with, or talking while your food is not the same as talk. We must have the manners to eat.
While eating (In the UK), we must have manners. Do not disturb or talk while eating. because it is not convenient to talk. We must have the courtesy to eat.
While eating (Thailand) we must have manners. Not to disturb or talk while you food because they are inconvenient to the conversation. We must have the courtesy to eating.