Students walk past posters introducing epidemic prevention measures at a senior high school in Nanjing, east China's Jiangsu Province, March 30, 2020. In eastern China's Jiangsu Province, students of grade 9 and 12 returned to school to prepare for entrance exams for senior high schools and colleges, respectively, after a long winter break, according to the provincial education department. (Photo by Liu Jianhua/Xinhua)
