The following are some famous phrases about the transition from a teenager to an adult: The love of a young man is pure love after adulthood, but it is full of impurities and utilitarians. The mark of a teenager's transition to adulthood is that he is beginning to realize that he is no longer young and begin to think about the meaning of life. 3. Young people are easily lost in desire, while adults are more easily lost in the pursuit of material things. The transition from a teenager to an adult is a process from impulse to rationality, and also a process from emotion to rationality. One of the signs of the transition from a teenager to an adult is the gradual realization of one's responsibilities and obligations. The sign of a teenager's transition to adulthood is that he has begun to seek inner peace and learn to control his emotions. The transition from a teenager to an adult is a process from dependence to independence, and also a process from fragility to strength. The sign of a teenager's transition to adulthood is that he has begun to learn to think and judge independently and no longer blindly follow the opinions of others. The sign of a teenager's transition to adulthood is that he is gradually accepting reality and beginning to seek solutions to his problems. The transition from a teenager to an adult is a process from fantasy to reality, and also a process from innocence to maturity.