First of all, let's look at Du Fu's Spring Hope:
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.
Sad state, can not help but burst into tears, amazing birds, leaving sorrow and hate.
The war lasted for more than half a year, and letters from home were rare, with a hundred thousand gold.
Twisting with melancholy, scratching my head and thinking, the more I scratch my white hair, I can hardly insert a hairpin.
This poem expresses Du Fu's description of the suffering caused by the Anshi Rebellion and the war, and also depicts the prosperous scene of the Tang Dynasty. In this poem, Du Fu vividly describes the lush and colorful spring in the city. With the sentence of "the plants are green in spring", the bustling scene of the city is written, and at the same time, under the lens, the desolation of warlords fighting and people being displaced is set off.
Next, let's take a look at Bai Juyi's Farewell to Ancient Grass:
The long grass is so lush that the withered grass will thicken the color of the grass every autumn and winter.
Wildfire can't burn it out, but the spring breeze can revive it.
Weeds and wild flowers are all over the ancient road, and the end of the grass in the sun is your journey.
I once again sent my bosom friend, and the thick grass represented my deep affection.
This poem takes the prosperous scene of the Tang Dynasty as the background and describes the grassland scenery in the upper reaches of the Yellow River. Bai Juyi begins with "the boundless grassland", describing the vastness and momentum of the natural environment of the grassland, while "wildfire never quite consumes them, the spring breeze is high" shows the natural strength and vitality of the grassland. Through the description of the natural environment, the prosperity and prosperity of the Tang Dynasty are compared, which makes the whole poem more euphemistic and moving.