Spring is still chilly, but when summer comes, cold doesn't last long. This cold is not reliable;

Autumn, an autumn rain and a cold, that warmth is only a temporary illusion. Just like the moon shining on the sun in the morning, just like the gorgeous flowers before the storm, unreliable;

The old man's health is lucky, but the machine has worn out and should be overhauled. Although it can persist for a period of time, it cannot violate objective laws. After all, it is unreliable.

A king's pet is like a tiger. Since ancient times, kings have held the power of life and death, and their emotions are moody. They do things from their own emotions, and their sacred intentions are unpredictable. Moreover, the emperor's love is not just a matter for two people or two families. The love of the emperor is not the love of father and son, nor the love of filial piety, but the inheritance of the throne, which is calculated and weighed; The emperor's love is not a confidant, but the majesty of the country and the gift of the monarch and the minister. The emperor's love is a country, a world and a politics, which involves countless sorrows. How can such feelings last for a long time?

The meaning of this sentence is similar to the impermanence of Buddhism. Not only are these four things unreliable, but everything in the world is unreliable. They are all impermanent, and there is nothing that remains unchanged for a long time. This is also the source of pain and trouble.