Photo taken on Jan. 10, 2021 shows Cao Ziyang (R), a high-speed train conductor, helping a passenger board the train. Working as a conductor of high-speed trains in Jinan section, Cao has been fighting against the COVID-19 epidemic since its beginning. He delivered epidemic prevention supplies to Wuhan many times in 2020, and has been working as volunteer in the community he lives in. (Xinhua/Wang Kai)