A staff member (1st L) from Uzbekistan registers with the help of volunteers at the registration center for the 18th meeting of the Council of Heads of State of the Shanghai Cooperation Organization (SCO) in Qingdao, east China's Shandong Province, June 4, 2018. (Xinhua/Wang Nan)

Volunteers greet guests at the registration center for the 18th meeting of the Council of Heads of State of the Shanghai Cooperation Organization (SCO) in Qingdao, east China's Shandong Province, June 4, 2018. (Xinhua/Jiang Kehong)

A staff member (1st L, front) from Uzbekistan registers with the help of volunteers at the registration center for the 18th meeting of the Council of Heads of State of the Shanghai Cooperation Organization (SCO) in Qingdao, east China's Shandong Province, June 4, 2018. (Xinhua/Jiang Kehong)