Why do you have to learn to crawl before you can walk and run? This is a growing life process, and it must be done. This is a physiological phenomenon of human beings, because people can't run at birth. After all, people are born with only a little weight, and they can't run when they are born. He must learn to crawl slowly before he can stand up and walk again. He can't run until he is stable. This is the process of human growth, that is, he can run when he is born. Then he became a fairy, which is impossible. In any case, he must learn to climb first, then walk, and then run. This is the most basic physiological process in one's life.