People look at an underwater robot during an intelligence science and technology exhibition in north China's Tianjin, May 17, 2018. (Xinhua/Li Ran)
In pics: view inside greenhouses in N China's Hebei
In pics: curtain wall project of sky corridor in SW China's Chongqing
Making traditional handicrafts increases income of local women in SW China's Guizhou
Over 7,000 heavy-haul freight train trips made on Watang-Rizhao Railway in 2018
Snow scenery of Washington D.C.
Frosty scenery seen in Tianjin