Source "Yuefu Poems and Long Songs": "When will a hundred rivers go east to the sea and return to the West? If you don't work hard, the boss will be sad. " This motto is taken from the ancient poem Long Songs in Han Yuefu. The original poem goes like this: "Sunflowers in the green garden bask in the sun. Spring fills the earth with hope, and everything presents a scene of prosperity. I am always afraid that when the cold autumn comes, the trees in Ye Er will turn yellow and the grass will wither. When will all rivers enter the sea and return to the west? If you don't work hard, the boss will be sad. " It can be seen that the last two sentences are the conclusion of the whole poem and the main theme of the poet's poetry. In the poem, the image of sunflower in the garden with warm spring flowers and withered autumn colors is used to describe the beauty of life in youth and the misery in old age; The metaphor of the passage of time and the eastward flow of the river will not stay for one person, but only for these last two warnings.