When we point a(手指) or make a face, people know this is(身体,躯干) language. Sometimes the same body language has different meanings in different(文化).
In China, people greet each other with heads(点头), smiles, hands(摇晃) and so on. Even good friends(握着,使不动) hands for a short time.
In English-speaking countries, people usually hug or(亲吻) each other in public. People in America greet each other with a handshake in a formal discussion (讨论) The handshake must be strong. If the handshake is weak, it means "not friendly".
(学习) body language is not easy. If you don't know what to(做,干), it is the most important for you to(微笑).