The second personality is like a man's Adam's apple getting bigger, a woman's chest getting bigger, a woman's menstrual flow and a man's nocturnal emission starting to grow pubic hair.

The third sexual characteristic refers to the social and psychological differences between men and women except physical differences. It is the characteristics of men and women whose social influence is gradually formed, such as hairstyle, decoration, gait and posture, personality characteristics and so on. These different characteristics of men and women are gradually formed under the influence of the acquired social and cultural environment, which we call "the third sexual characteristic".