Aerial photo taken on March 26, 2019 shows a worker walking on the roof of the International Pavilion at the site of the International Horticultural Exhibition 2019 Beijing China (Expo 2019 Beijing) in Yanqing District of Beijing, capital of China. The 2019 Beijing International Horticultural Exhibition is slated to kick off on April 29, 2019. (Xinhua/Zhang Haofu)