First of all, extroversion and introversion are relative definitions, and there is no clear boundary. Extroverts' psychological activities point to the outside world, showing more curiosity and exploration, cheerful personality and like to communicate with others. But when they are alone, thinking and living, most of their thoughts are expressed through language, and then they may be further transformed into actions. Introverts' psychological activities point to the inner world, showing silence. Silence (that is, you don't like to talk), love to think, etc. Most of their thinking is done internally, and they don't just say what they think. Introverts also have extroverts, such as being with good friends and like-minded people. If they have a common topic, they will talk more accordingly.