(210120) -- SHIJIAZHUANG, Jan. 20, 2021 (Xinhua) -- Cao Zepan (C) works at the construction site of Huangzhuang Apartment COVID-19 quarantine center in Shijiazhuang, north China's Hebei Province, Jan. 19, 2021. Cao Zepan, a technician of China Railway 14th Bureau Group, went to Shijiazhuang to aid the construction of the COVID-19 quarantine center with his colleagues on Jan. 16. Born in 2000, Cao is new but devoted to his work. Cao and other workers stick to their posts despite harsh winter weather, and work around the clock to guarantee the on-time completion of the construction. "This is the first key project I have ever participated in, and I am proud to be one of the 4,000 workers here," Cao said. (Xinhua/Mu Yu)