Moral: Good luck will not always belong to you, good luck will not always follow you, and good things will not always accompany you. Your life can't be smooth sailing forever, and you can't drink cold water all the time. This is the same as thirty years in Hedong and thirty years in Hexi, which shows that a person's life is ups and downs and cannot be dull forever. To put it bluntly: now you are lucky and I am unlucky, but you will not be lucky forever, and I will not be unlucky forever. There will always be an upside down day. It's my turn to be lucky, but you're unlucky.