Guo Mingchang, a successor of Qi writing brush making technique, teaches his skills to pupils in Dawang township of Guangrao county, East China's Shandong province, June 4, 2017. Dawang's Qi writing brush was listed as an intangible cultural heritage of Shandong in 2013. The annual output of writing brush in the town has reached about six million. [Photo/Xinhua]