This is a sentence from Li Bai's "Bin Ge Xing Shang Xinping Chang Shi Xiong Can". I will try to answer it. Ning Zhi: I didn’t expect it, how could I know. Wandering apartment: temporary residence, wandering. Change of light: changes in light and shade, here refers to seasonal changes. The whole sentence means that we didn't know that we would come here in late autumn this time. When combined with the previous poem, it means that the last time we passed through this place was in summer, but this time it is autumn, and the weather has changed. This is just a literal meaning, but it actually alludes to the changes in human relationships. Li Can may not be Li Bai's brother. It seems that he received Li Bai last time, but this time he was extremely cold. Although Li Bai realized it, he still had a little hope, but the fact was that it didn't work.