When you don't speak, you may be still communicating. It is true that you may not wish to say anything. But your very silence may show your wish to be left alone or to stay uninvolved, which is the message you want to send. So it has been said that while we speak with our vocal organs, we  _ with our whole bodies. All of us communicate with one anther nonverbally  , as well as with words. Sometimes we know what we are doing with the use of gestures such as the thumbs-up sign to indicate that we approve. But most of the time we are not aware that we are doing it.  Body language serves a variety of purpose. Firstly it can replace verbal communication, as with the use of gesture. Secondly, it can modify   verbal communication. Loudness and tone of voice is an example here. Thirdly it regulates social interaction: turn taking is largely governed by non-verbal signals. Fourthly it conveys our emotions. Finally it conveys our attitude towards ourselves and towards the people we are communicating with.  _ is particularly important for successful cross-cultural communications. Every culture has its own body language. So in order to achieve a more successful cross-cultural communications, we heed not only what to say but also how to say it appropriately. Observation shows that a truly bilingual person switches his body language at the same time he switches language. Body language varies  _  .
from culture to culture from year to year from time to time from person to person