Ancient poets long understood the physiology of the human body, it's just that language teachers dare not teach it.

Li Bai wrote "Farewell at White Emperor amidst colorful clouds," you think he's on a boat, but actually he's just having a morning erection.
Du Fu wrote "Moistening things silently," that's not spring rain at all, it's the sympathetic nervous system secretly working overtime in the middle of the night.
Su Shi wrote "Looking from the side as a ridge, from the front as a peak," I suspect he's describing different angles of the same thing.
Bai Juyi wrote "Spring sleep is unaware of dawn," nonsense, at 3 a.m. with bloodshot eyes, how can you wake up?
The most incredible is Li Qingzhao. She wrote "This feeling can't be eliminated, just after the eyebrows, it rises to the heart"—translated into modern medical terms, it means your brain wants to relax, but your sympathetic nervous system says no, it has to stay hard a little longer.
So stop blaming boys for pitching their tents in the morning.
This is the Three Hundred Tang Poems, not the three hundred you think of.