Passengers take a driverless train of the newly-opened Sydney Metro Northwest at Chatswood Station in Sydney, Australia, May 26, 2019. Sydney's new driverless northwest Metro opened on Sunday. (Xinhua/Bai Xuefei)
In pics: great spotted woodpecker in NE China's Liaoning
Scenery of Mount Emei in China's Sichuan
View of terraced field in C China's Hubei
Water lilies in bloom
Highlights of Kirtland Air and Space Fiesta in U.S.
In pics: summer farm work across China
Scenery of Ra'og Lake in China's Tibet
12th Hebei Folk Culture Festival held in Shijiazhuang