Sun Ranweng's couplet was written in A.D. 1765. At that time, the officialdom was corrupt and the people were poor. The poet felt it at once. He touched the scene while writing the scenery, attacked the rule of the feudal dynasty, and revealed the law of the inevitable decline of the feudal dynasty, which was also the foreshadowing of the demise of the Qing Dynasty. He regards the orthodox dynasty as a fleeting illusion and the "great achievements" of emperors as "broken monuments" in Sunset. At that time, this was an obvious rebellious thought, which was suspected of "crime" and was bound to be tolerated by those in power and their accomplices. Because of the popularity and popularity of Touweng's couplets, they dare not publicly revoke the couplets, so some people wrote two pairs of long couplets of Daguanlou by tampering with words, imitating the format of Sun Ranweng, in an attempt to replace the original ones by changing their ideological connotations and use them for feudal rulers. But always self-defeating, leading to a lot of jokes, handed down with the long face, but expanded the influence of the bearded Weng's long face.

There is a magnificent couplet in Daguanlou. The first part is about the scenery of Dianchi Lake, just like the travel notes of Dianchi Lake; The second part of Yunnan History is like an essay on reading history. The word Quanlian 180 is like a vivid, colorful and affectionate parallel prose, with witty remarks like pearls and catchy words. The couplet is rich in images and full of emotions, and it is known as the first long couplet at home and abroad.

The first couplet highlights the word "reward", appreciates the indescribable beauty and depicts a landscape painting with Dianchi Lake characteristics. When the author went upstairs, he first wrote about the vast and boundless Yunnan Sea in front of him, and the joy of the author to look at the sea by opening his skirt and his headscarf. Then write about the landscape around Daguanlou: Jinma Mountain in the east is like the god of running horses, Bijia Mountain in the west is like a phoenix with wings, Snake Mountain in the north is like a crawling snake, and Heshan Mountain in the south is like a crane with wings. Looking around the building, I returned to the vast Dianchi Lake, with crabs and conch-shaped islands dotted with willows swaying like girls' hair. Clusters of water plants and rustling reeds are like colorful feathers of birds dotted with clouds and Xia Hong in the water. Earlier, after seeing Dianchi Lake and the surrounding mountains, the author once expressed the feeling of literati, why not choose the high-rise building of this resort to enjoy it. Here, after describing the beautiful scenery in front of us, the author sighs again: Don't waste the beautiful scenery-fragrant rice all around, sparkling, lotus flowers in the midsummer of June, willows in the spring breeze of March. The author expresses his feelings by writing about the scenery, and his relaxed and happy mood emerges from the paper.

The second part summarizes the history of Yunnan, focusing on the word "sigh". Tracing back to the source, the author tells the inevitable law of historical development and changes, and shows a fascinating historical picture. After seeing the beautiful scenery in front of him, the author immediately recalled the ever-changing history of Yunnan and expressed infinite emotion-all the heroes of past dynasties have quietly flowed away with the long river of history: Emperor Wu of the Han Dynasty, who regarded heroes as a generation, dug Kunming Pool in Chang 'an to train the water army in order to get through the southwest artery; Emperor Datang once canonized Nanzhao, erected iron pillars, and praised merits; Song Taizu actually waved to her husband, demarcated Xinjiang and made Dali autonomous; Yuan Shizu Kublai Khan went from Gansu to Sichuan, occupied Yunnan, destroyed Dali, conquered Tubo and successfully cut the Central Plains. This series of magnificent scenes exhausted the efforts of the heroes to move mountains and rivers. However, all this, like the morning clouds wandering outside the curtain of the colorful building, disappeared in the yellow rain rustling before the bead curtain was rolled up. Those words of praise for merit follow the broken monument. Buried in the sunset and the smoke of the farmhouse. All we have left is the bell from the temple and the fisherman's light by the river. Two rows of autumn geese flew south into the sky, and the literati who slept in the mountains woke up, and the frost was clear. How can this not make people sigh!

Long couplet lyrical narrative, distinct levels, scene blending; The antithesis is neat and the words are refined; The connotation is beautiful, colorful, delicate and imposing. It is an immortal masterpiece in the history of couplets and has great influence. The couplets in Daguanlou are a mirror of poetry, painting and history, revealing the historical fate of the inevitable decline of the feudal dynasty. This vision is hidden between the lines of couplets. Because of this, couplets have been tampered with and changed many times in history, but not fade away did. On the contrary, it further emphasized its position in the history of couplets.