A medical worker takes a swab sample from a resident for nucleic acid test of COVID-19 at a test site in Dalian, northeast China's Liaoning Province, July 27, 2020. (Xi
File Photo: Students keep a safe distance from each other before entering the Tonghui primary school in Shenyang, northeast China's Liaoning Province, June 8, 2020. (X
简体中文
