People look at an unmanned helicopter at the 21st China Beijing International High-tech Expo in Beijing, capital of China, May 17, 2018. The expo has drawn more than 1,600 companies from 14 countries and regions to discuss the industrialization of high-tech products. The four-day event will feature 12 promotional sessions and 10 seminars, according to the organizer. (Xinhua/Luo Xiaoguang)