This combo photo shows a train attendant mopping in a train carriage that travels from Urumqi to Kashgar in northwest China's Xinjiang Uygur Autonomous Region, March 10, 2005 (left, photo taken by Sadat); and a worker cleaning a bullet train carriage at a depot in Wuhan, central China's Hubei Province, early on Feb. 10, 2011 (right, photo taken by Cheng Min). (Xinhua)