Spoken language is usually used to communicate with each other.As a matter of fact,voiceless language (无声语言) ,especially body language,is as important as spoken language.Long before spoken language was used,muman had bagun to talk to each other with body language.
Communication by means of movement and gesture (手势) helps one read what another want to tell him.A sweet smile,for example,can calm your friende who is unhappy.When there is too much noise,it is easier to communicate using body language.
When people show kindness with each other,they turn their upper bodies toward each other,with their shoulders squarely parallel (端平肩膀) and there is more eye contect.If they disagree,they unconsciously turn their bodies away from each other.
Therefore,words cannot tell you what body language can.