Changhu: It refers to Lipeng Lake, which is Poyang Lake in Jiangxi Province today. Its shape is long and narrow from north to south.
"Depression" sentence: It means that all kinds of natural scenery are in a state of depression.
The explanation of "crossing the long lake in August is bleak" is: crossing Lipeng Lake in August, where the scenery is bleak.
The function of the poem "Crossing the Long Lake in August, the sky is bleak" is to reflect the author's inner bitterness through the depression of the scenery.
Nankang Wang Hu Pavilion is one of the poems of Su Shi, a writer in Song Dynasty. Nankang, Kang Jun's guide, is in Jiangxi Province today. In the first year of Song Zhezong Shaosheng (1094), Su Shi passed through Dangtu, Anhui Province on his way to Yingzhou, and received a letter of relegation to Huizhou, so he let his second son Su Chang stay in Mai Su, the eldest son of Yixing, and went to the cloud with his concubine, and his third son Su Guo went to Huizhou. Su Shi wrote this poem when he passed Nankang in August.