1. to conduct oneself in a manner that is socially acceptable, polite, and appropriate
The children were asked to behave properly during the ceremony.
Pediu-se às crianças que se comportassem adequadamente durante a cerimônia.
2. to act in accordance with established rules or standards of conduct
If you want to succeed in this company, you need to behave properly.
Se quer ter sucesso nesta empresa, precisa comportar-se adequadamente.