Write eight jars of water, and the inkstone (face) stains (old) pool is black; What does "Bo" mean by taking hundreds of parents (Chang) and making them fly like dragons and phoenixes?
If I am not mistaken, this should be a passage describing Wang Xizhi. "When writing eight tanks of water, the inkstone (Yan) dyed the pool black (old)" means that he wrote eight tanks of water in calligraphy and dyed the whole pool black. "There are hundreds of teachers (often), and dragons and phoenixes fly" means that he has taught hundreds of teachers and finally became a generation of calligraphers.