What are the meanings of the first four ancient poems in Unit 6, Grade 6 of Chinese in primary schools?

The Book of Songs Cai Wei: When going to war, Yangliuyiyi was blown by the wind. Now on the way back, the snow is flying all over the sky.

Delighting in Rain on a Spring Night: Haoyu knows that the rain in solar terms is the time when plants germinate and grow. It falls quietly at night with the spring breeze, silently nourishing all things on the earth. On a rainy night, the fields were dark, and only the lights on the river boat were exceptionally bright. After dawn, looking at the flowers with rain, they are beautiful and red, and the whole Jinguan City has become a world of flowers and flowers.

"Walking on the Yellow Sand Road at night on the Xijiang Moon": The bright moon on the horizon rises to the treetops, scaring the magpies perched on the branches. The cool evening breeze seems to blow the cicadas in the distance. In the fragrant rice, people talked about the harvest year, and there were waves of frogs in their ears, as if to say the harvest year. There are faint clouds in the sky, twinkling stars appear from time to time, and light rain begins to fall in front of the mountain. Turning the corner, Maodian suddenly appeared in front of him.

Patio sand autumn:

The sun has gradually set in the west, and the sunset glow on the horizon has gradually begun to dissipate, leaving only a few dim colors, reflecting how lonely the quiet village in the distance is, dragging a long shadow. The smoke from the kitchen rose faintly, and several black crows perched on the rickety old tree, occasionally making a few miserable cries. Suddenly, a wild goose flew down in the distance and crossed the sky. Look down from a distance. Frosted grass, flaming maple leaves and golden flowers are swaying together in the wind, and their colors are almost enchanting.