A train of the Guangzhou Metro Line 18 is seen at the Longzhen train depot for hot-running test in Guangzhou, south China's Guangdong Province, March 3, 2021. The electric train, with a maximum designed speed of 160 km per hour, carried out the first hot-running test in the small hours of Thursday morning, in order to conduct a comprehensive inspection of the subway power supply, signal, communication, line, and electromechanical system of the line. (Xinhua/Liu Dawei)