Actors perform during the opening ceremony of the 4th Silk Road (Dunhuang) International Cultural Expo and the 9th Dunhuang Tour-Silk Road International Tourism Festival in Hezuo, northwest China's Gansu Province, July 30, 2019. The expo and the festival kicked off here on Tuesday, aiming to promote cooperation and exchange among countries and regions along the silk road. (Xinhua/Ma Ning)