According to the author, people tend to______.

The ways of behaving are different in various societies.(14)People from one country may think the behaviors of people from another country to be bad. Some people may like to open a gift in the presence of the giver, but others may not. Some people may like to eat as quietly as possible, but others may like to open conversations while they are eating. However, the idea of all codes of behavior is to make life flow smoothly. No one way of behavior is right or wrong and, also, no one way can be called "good" or "bad" manners except as a society defines it.(15)In the Western world, there are some special behaviors that people have to follow. No one should open a closed door without knocking. No one can enter without being asked to go in a private house, unless it is one’s own. Westerners always teach their children to say "thank you" when gifts are given to them. To westerners, eating noisily or belching at the table is considered as bad manners, and yet in some societies these acts are the proper way to express your appreciation of the food offered to you.(16)So it is likely for one to make foolish mistakes if you don’t know the way to behave in other countries.