A student reads a book in the library of Xinshi Primary School of Shijiazhuang, north China's Hebei Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Zhang Xiaofeng)

A man reads at Xinhua Bookstore in Zunyi, southwest China's Guizhou Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Luo Xinghan)

A child reads in a library of Bijie City, southwest China's Guizhou Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Shang Yujie)

People read books in the library of Changli County in Qinhuangdao City, north China's Hebei Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Yang Shiyao)

Students of the Central Primary School read in the campus in Gangbian Township of Congjiang County, southwest China's Guizhou Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Luo Jinglai)

People read in a bookstore in Zaozhuang, east China's Shandong Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Sun Zhongzhe)

A student of Jianning Primary School reads a book in a book bar in Haizhou District of Lianyungang City, east China's Jiangsu Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Geng Yuhe)

Children read a book in Qianxi County of Bijie City, southwest China's Guizhou Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Zhou Xunchao)

A student reads a book in the morning in the No.2 High School of Zunhua City of Tangshan, north China's Hebei Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Liu Mancang)

People read in a bookstore in Zaozhuang, east China's Shandong Province, April 23, 2019. Various activities have been held across China for the World Book and Copyright Day, which is celebrated yearly on April 23 to promote reading, publishing and copyright. (Xinhua/Sun Zhongzhe)