An interpreter introduces the guided-missile destroyer Guiyang of the Chinese People's Liberation Army (PLA) Navy to visitors during a warship open day event in Qingdao, east China's Shandong Province, April 24, 2019. A warship open day event was held on Wednesday in Qingdao, as part the multinational naval events marking the 70th founding anniversary of PLA Navy. (Xinhua/Luo Xiaoguang)