Photo taken on Dec. 27, 2017 shows Fuxing bullet trains in North China's Tianjin municipality. A new train diagram will be put into operation in China from Dec. 28, 2017. [Photo/Xinhua]

Passengers walk on the platforms of the train station of Yantai city, East China's Shandong province, Dec. 27, 2017. [Photo/Xinhua]

A bullet train pulls out off the train station of Yantai city, East China's Shandong province, Dec. 27, 2017. A new train diagram will be put into operation in China from Dec. 28, 2017. [Photo/Xinhua]

Workers examine a Fuxing bullet train in North China's Tianjin municipality, Dec. 27, 2017. [Photo/Xinhua]