Stephanie Pollack (1st R), secretary of Massachusetts Transportation Department, takes a ride on a new Orange Line train manufactured by China Railway Rolling Stock Corporation (CRRC) at Wellington Yard in Medford, a residential and industrial suburb of Boston, the United States, on May 15, 2018. New subway cars designed and manufactured by CRRC are undergoing tests and will be ready to take passengers in Boston by the end of 2018, said local officials on Tuesday. (Xinhua/Li Muzi)