What is the meaning of "two Huang Liming and Liu Cui" in Du Fu's quatrains? What kind of atmosphere does the whole poem create?

Hello, I'm glad to answer your question!

Quatrain

Du Fu

Two orioles sing green willows,

A line of egrets rose into the sky.

Autumn snow in Xiling, in front of the window,

Mambo Wu Dong Wan Li Ship.

Green willows sway by the river, attracting playful orioles. Two lovely orioles kept singing, as if praising the beauty of willow trees. Looking up, many white and lovely egrets lined up neatly and flew into the blue sky together. It is really cute. Looking out from the small window, the mountain in the west is still covered with snow, and it seems that it will never melt and always cover the top of the mountain. Then I opened the door and looked at the lake in the distance. I looked at the Wu Dong warship about to sail. Rows are really like dragons in the water!

Outside, the willows are green and dripping, and the willow branches are dancing in the wind. Two orioles are chasing among the willows, singing sweet songs. The poet was amused, so he wrote a vivid poem "Two orioles singing green willows". Then look up at the sky and see rows of egrets flying freely in the sky, as if welcoming the blue sky. This will naturally make the poet feel that "a line of egrets is on the sky". From near to far, these two sentences have a broad vision. The poet's eyes, like the lens of a camera, turned to the opposite Xiling (Minshan). This magnificent Xiling is covered with snow and will last for thousands of years. It is like a snow barrier, across the west. Although Xiling is large, this small window can have a panoramic view of the snow in Xiling. The poet summed up the snow scene he saw with the phrase "window contains", which was extraordinary in momentum. Then the poet's eyes fell from the mountain to the Minjiang River in front of the door and saw many merchant ships moored along the river. These merchant ships often travel between Shu and Wu in the lower reaches of the Yangtze River. There is a Hejiang Pavilion near the Caotang, where people from Shu to Wu get on board. According to historical records, during the Three Kingdoms period, Wei Fei was sent to Wu Dong, where Kongming once saw Wei Fei off. He said to Wei Fei: "The trip to Wan Li begins with a single step." Later generations called a nearby bridge "Wan Li Bridge". Of course, Du Fu was familiar with these anecdotes, so he integrated scenery and historical facts into his poems and got the sentence "Boating in Dongwu Wan Li".

The whole poem creates a fresh and relaxed atmosphere and expresses the author's love for spring and nature.