What does it mean to scatter a setting sun in the water, half river rustling and half river red?

"A setting sun is spreading in the water, half the river is rustling and half the river is red" means: the setting sun is reflected on the river, and the glow is shining; Half of the river is dark blue and the other half is red.

This is a poem written by Bai Juyi, a poet in the Tang Dynasty, in Mujiang Song.

The whole poem of Ode to Mujiang is as follows: A setting sun is spreading in the water, half river rustling and half river red. The loveliest thing is the ninth day of September. The bright pearl's bright crescent moon is shaped like a bow.

Literal meaning of the poem: the setting sun is reflected on the river, sunny and sparkling; Half of the river is dark blue and the other half is red. The loveliest thing is the night on the third day of September, with dew like beads and crescent like a bow.

Appreciation of the whole poem:

The first two sentences are about the river at sunset. "A sunset is spreading in the water". The sunset shines on the river, but it means "spreading" instead of "taking pictures". This is because the "sunset" is very close to the horizon, almost touching the ground, and it really looks like it is "paved" on the river. The word "shop" also appears euphemistic and gentle, describing the unique softness of the autumn sunset, giving people a cordial and leisurely feeling. "Half the river is rustling, half the river is red", the weather is clear and windless, the river flows slowly, and there are tiny ripples on the river. The part that receives more light shows "red"; Where there is little light, there is dark blue. The poet grasped the two colors on the river, but showed the scene that the river was sparkling at dusk and the color changed rapidly in the sunset. The poet was intoxicated and put his happiness in the description of the scenery.

The last two sentences are about the night scene when the new moon rises. The poet lingered until the early moon rose, the cool dew fell and a better realm appeared in front of him. The poet leaned down and saw the grass by the river covered with crystal dew. Dewdrops on the green grass are inlaid on the green grass like pearls. With the metaphor of "real pearl", not only the roundness of dew is written, but also the luster of dew shining under the new moon. The poet looked up again and saw a crescent moon Ran Ran rising, just like a delicate bow hanging in the blue sky. The poet condensed the two wonders of heaven and earth into a poem-"The dew is like a real pearl, and the moon is like a bow". From a crescent moon bent like a bow, the author remembered that it was "the third night of September", and could not help but blurt out his lovely praise for it, expressing his feelings directly, pushing his feelings to a climax and causing waves in his poems.