Photo taken on May 23, 2018 shows a subway cabin decorated with elements of Qingdao in Qingdao, East China's Shandong province. The coastal city will host the 18th summit of the Shanghai Cooperation Organization (SCO) in June. [Photo/Xinhua]

A couple pose for wedding photos on a beach in Qingdao, East China's Shandong province, May 4, 2018. The coastal city will host the 18th summit of the Shanghai Cooperation Organization (SCO) in June. [Photo/Xinhua]

People have meal at a restaurant in Qingdao, East China's Shandong province, May 18, 2018. The coastal city will host the 18th summit of the Shanghai Cooperation Organization (SCO) in June. [Photo/Xinhua]