In the poem "Farewell to Friends at Jingmen Ferry", Li Bai used figurative rhetoric to contrast the calmness of the river, showing the vastness of the river bank and the high air billow.

The moon rises like a mirror, and the sea clouds twinkle like palaces.

The moon reflects the river, just like flying a mirror tomorrow; Clouds turned into blue sky, creating a mirage.

All this is so quiet, the sky is so vast, the river is so calm, and the water and sky are the same. Show the sky and be full of romance.

Therefore, it is this sentence.