There is a couplet in Zhuge Liang's former residence in Longzhong, Xiangyang. Help me explain the meaning of couplets.

The first part of the book is about China's ancient writers: Nan Huajing (Zhuangzi), Xiang Rufu (the representative figure of Han Fu), Ban Guwen (Ban Gu's Han Shu is second only to Historical Records), Shi (Sima Qian's Historical Records is the swan song of historians, Li Sao has no rhyme) and Xue (the colorful paper and poems invented by Xue Tao, a talented woman in the Tang Dynasty, are praised by the world). Shaoling poems (poems by poet Du Fu, not a busy word), rubbings (paintings by Wang Wei, which contain poems), Qu Gigi Lai Sao (Qu Yuan's Li Sao, needless to say), ancient and modern stunts (the above humanities are all first-class talents in ancient and modern times).

The second part is about great rivers and mountains: one day in the sea (the sunrise at sea seen in Jieshi, east of Cao Mengde), Chicheng Gorge (Chicheng, a famous town outside the Great Wall, is famous for its Danxia landform), Emei Fog (the top of Emei Mountain is a sea of clouds and fog, which is spectacular), Wushan Cloud (the dream that Wushan Cloud has entered) and Dongting Mingyue (the moon of Dongting Lake, floating and jumping, with a heavy static shadow ... Ji Kang sang a song "Guangling San", "Lushan Waterfall" (the waterfall on Lushan Mountain goes straight down to thousands of feet), and the wonders of the universe (these famous mountains and rivers are wonders of the universe (unfortunately, the tickets are too expensive)).