Commentary: In Qian Shan, there are towering trees and cuckoos singing. ("Wanhe" and "Qianshan" are intertextual rhetorical devices: Wanhe in Qianshan is full of trees and azaleas, not just Wanhe's trees and azaleas in Qianshan. )
The first sentence is static and the second sentence is dynamic; The first sentence is written in form, and the second sentence is written in sound; The previous sentence gives us a sense of silence and solemnity; The last sentence has a feeling of relaxation and pleasure. Wanhe and Qianshan have a large writing space, and the trees are towering for a long time, and the cuckoo is a bright atmosphere.
These two sentences are about what you saw and heard when you traveled in the mountains, and the fun of traveling in the mountains is naturally included in the description.