Photo taken on Aug. 26, 2020 shows staff members cleaning tables in a canteen at Jiangbei High School, Beibei District of Southwest China's Chongqing Municipality. The school has stepped up epidemic prevention and control measures ahead of the new semester. (Photo by Qin Tingfu/Xinhua)

Photo taken on Aug. 26, 2020 shows a staff member setting up barricades at Jiangbei High School, Beibei District of Southwest China's Chongqing Municipality. The school has stepped up epidemic prevention and control measures ahead of the new semester. (Photo by Qin Tingfu/Xinhua)

Photo taken on Aug. 26, 2020 shows a staff member placing signs at Jiangbei High School, Beibei District of Southwest China's Chongqing Municipality. The school has stepped up epidemic prevention and control measures ahead of the new semester. (Photo by Qin Tingfu/Xinhua)