Different people use different languages. We Chinese speak Chinese, and, most of us are learning a foreign language. But there is another kind of language we need to know --- the language of the body. All over the world, people "talk with their hand, with their heads and with their eyes." When Japanese people meet, they bow. When Indians meet, they put their hands together. What do American and British do? Americans are more imformal  than the British. They like to be friendly. They use first names, they ask questions and they talk easily about themselves. When they sit down, they like to relax in their chairs and make themselves comfortable. British people are more reserved . They take more time to make friends. They like to know you before they ask your name. When British or American people meet someone for the first time, they shake hands. They do not usually shake hands with people they know well. Women sometimes kiss their women friends, and men kiss women friends (on one cheek only). When a man meets a man, he just smiles, and says, "Hello." Men do not kiss each other, or hold hands. Even fathers and sons do not often kiss each other. In the passsage, the writer thinks that body language is   _  .
uselss difficult quite easy important