What do you mean, the mountain doesn't swear to the four seasons?

The meaning of this sentence is that the forest does not promise four seasons, but it flourishes and withers with the seasons.

From the point of view of natural law, the plants in mountain forests do not promise to flourish or wither with the change of seasons. Just follow the laws of nature and change with the seasons. In spring, everything recovers, and plants in the mountains begin to grow and sprout; In autumn, the temperature drops and plants begin to wither.