Describe Zhang Xu's cursive script.
Zhang Xu's hobby is wine. When writing a book, he often gets drunk, makes a hullabaloo about and even splashes ink, so he is called "Zhang Dian". Based on Wang Shu and Zhang Zhi, he developed the traditional cursive script and created a new realm of cursive script with Huai Su. At that time, people complained about the early schools, but only Zhang Xu had no objection. Tang Wenzong called Li Bai's poems and songs, Pei Min's swordsmanship and Zhang Xu's cursive script "three musts". Zhang Xu claimed that his book "I first saw the princess arguing with her husband, and I heard that it was a good result." Seeing Gong Sundaniang's sword dance, he won his god. "It can be seen that his cursive script is inspired by nature and social life, rather than simply playing with pen and ink skills at the desk. Du Fu wrote in his poem: "The self-proclaimed minister is Brewmaster, and Zhang Xu made three cups of grass sacred biography, took off his hat and appeared in front of the princes, and put pen to paper like a cloud. "