The meaning of "Smoke cage, autumn water, moon cage and sand" means: the vast cold river is filled with misty smoke, and the clear brilliance of the bright moon shines on the white sand. Smoke: smoke. The source of "Smoke Cage, Autumn Water, Moon Cage Sand": Du Mu's "Po Qinhuai" in the late Tang Dynasty. Appreciation of "Bo Qinhuai": This poem is based on the history of Empress Chen (Chen Shubao) who eventually lost his country due to his pursuit of debauchery and pleasure, and satirizes the rulers of the late Tang Dynasty who did not learn from it and died in a dream. It shows the author's incomparable concern and concern for the fate of the country. Feelings of deep concern.