"Putting pen to paper scares the wind and rain, and poetry cries" is the evaluation of Li Bai by Du Fu, a poet in the Tang Dynasty. This poem is from Du Fu's "Send Li Twelve Whites and Twenty Rhymes", which was created by Du Fu because he missed Li Bai.
These two sentences, "Putting pen to paper shakes the wind and rain, poetry makes ghosts cry", express Du Fu's appreciation of Li Bai's poetic talent and have a high evaluation. "A stroke of a pen scares the wind and rain" vividly expresses the majestic momentum of Li Bai's poems, while "Poetry makes people cry" reveals that Li Bai's poems and songs deeply touch people's hearts.