Duality is a rhetorical device that uses a pair of phrases or sentences with the same number of words, the same structure and symmetrical meaning to express two corresponding or similar or identical meanings.
Features: the language is concise, the sentence pattern is neat, the phonology is harmonious, and it is full of rhythm and musical beauty, which makes the two meanings complement each other and set off each other, enhancing the touching effect of the language.
So these two sentences belong to duality.
What these two sentences want to express is that the sun shines on the incense burner peak and purple smoke rises. From a distance, clouds are flying in the mountains, and strange mountains and trees seem to be wrapped in clouds. The most beautiful scenery in the world should belong to Huangshan Mountain.
This was changed by modern people from the Wanglushan Waterfall by Li Bai, a poet in the Tang Dynasty, and the rewritten poetry was to praise Huangshan Mountain.