How to write and interpret the cuckoo image in ancient poetry

The cuckoo, also known as Du Yu, Wang Di, Zigui and Bugu, was forced to give way to his courtier, Du Yu, king of Shu (Wang Di), and his soul became a cuckoo after his death. So the cuckoo in ancient poetry has become a symbol of desolation and sadness, which is often associated with bitterness.

Because crying seems to be "not as good as going home", it is often used to express feelings of missing hometown and expressing sadness without hatred; Borrow the image of cuckoo weeping blood to express the loyalty and patriotism of worrying about the country and the people; With the cuckoo's cry, the flowers in spring have fallen, and the poet also regrets the appearance of cuckoo, the flowers have fallen and the spring has gone.

Li Bai's "Difficult Road to Shu": "On a moonlit night, cuckoos crow and worry about empty mountains."

Bai Juyi's Pipa Trip: "The cuckoo cries and the snow ape mourns." Du Fu's sad cry always touches the poet's sadness.

Li Bai's "I heard that Wang Changling left to move to Longbiao Yao to have this letter" "When flowers bloom and fall, they all cry, and Wendao Longdu crosses five streams. I am worried about the bright moon, and I will go to Yelangxi with the wind. " Writing sentences is the scene of the eyes. In the bleak and desolate natural scenery, I feel sad to leave. Three or four sentences express infinite nostalgia and deep sympathy for friends with the rich imagination of sending affection to the bright moon.