A man takes physical examination before donating his blood at the Nanjing Red Cross Blood Center in Nanjing, east China's Jiangsu Province, March 4, 2020. Many residents in Nanjing volunteered to donate their blood ahead of "Lei Feng Day", which falls on March 5 every year, as a way to help others in remembrance of the soldier renowned for his generosity and altruistic deeds. (Xinhua/Ji Chunpeng)