You have to find out why he dropped out of school first. Do you think, a 20-year-old child, if he likes his major and this school, why would he want to quit school? So he decided to quit school for his own reasons, and this reason has overcome his fear. After all, it takes courage to drop out of school. Parents may object, classmates may talk, and teachers may discourage them. At the same time, he naturally has the pressure to find a job. As far as you are concerned, you are a teacher in his school. Is it possible that he feels not free enough because of this? In fact, children need to leave their parents when they grow up. If he stays with his parents for a long time, he sometimes feels watched, which may bring extreme depression. If so, you can pay less attention to him or even help him, and try to participate in his life as little as possible. Anyway, you have to listen to his reasons. If he really decides and your persuasion fails, then promise him. Besides, he just dropped out of school, not dropped out. If he regrets it within two years, he can continue to study, and the loss is not too great. If he finds a better life, it will be a surprise.