This is a natural phenomenon. Because the weather is clear and windless, the river flows slowly, and tiny ripples ripple on the river. Under the oblique light of the setting sun, the part with more light appears red; The part that is not illuminated by the sunset is turquoise. The poet captured the changes of these two colors on the river in the evening, showing the beauty of the river.
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Original text:
Mu Jiangsong —— Bai Juyi, a poet in Tang Dynasty
A sunset gradually sank into the river, half green and half green.
The loveliest thing is the ninth day of September. The bright pearl's bright crescent moon is shaped like a bow.
A sunset sank into the river, and the river was half green and half brilliant red. The loveliest thing is the night on the third day of September, with dew like beads and crescent like a bow.