Du Fu looked forward to the contrast of the author's sentence about the desolate and broken scene of trees.

Chang' an fell, the country was broken, and only the mountains and rivers remained; Spring has come, and the sparsely populated Chang' an city is densely forested.

The whole article revolves around the word "Wang", and the first four sentences are lyrical by taking advantage of the scenery. The poet set off the ruin of the country by describing Chang 'an, which is lush and sparsely populated. The first song "Although the country is divided, the mountains and rivers live forever" is shocking and has a sense of historical vicissitudes. Wrote the sad scene of the country destroying the city. The phrase "Where the petals have fallen like tears, and the lonely bird has sang mourning" personifies the flowers and birds, feeling that the country is divided and the national affairs are difficult, and the flowers and birds in Chang 'an are all shocked by tears. Write about spring with flowers and birds, hurt things, and express the sadness of national subjugation and parting with personification. Reflect the poet's patriotic feelings.