A staff member disinfects a canteen in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Darkhan)

Staff disinfect a classroom in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Darkhan)

Staff disinfect a teaching building in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Darkhan)

Staff disinfect a teaching building in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Darkhan)

A staff member disinfects a dormitory in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Liu Lei)

Staff disinfect a teaching building in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Liu Lei)

A staff member disinfects a dormitory in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Darkhan)

A staff member disinfects a corridor of a teaching building in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Liu Lei)

Staff disinfect a teaching building in No. 3 High School in Wuchuan County, Hohhot, capital of north China's Inner Mongolia Autonomous Region, March 29, 2020. The school carried out disinfection work for class resumption of students in their final year of senior and junior high schools. (Xinhua/Liu Lei)