These 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.