International Olympic Committee President Thomas Bach (front, R) shakes hands with a volunteer at the Main Media Centre of the 2014 Nanjing Youth Olympic Games in Nanjing, capital of east China's Jiangsu Province, on August 15, 2014. According to the Local Organising Committee, there are about 20,000 volunteers, most born in the 1990s, playing different roles in spectator services, competition services, medical services, food services, IOC members services, etc. with their vigor and hospitality. (Xinhua/Tao Xiyi)