Photo taken on April 20, 2020 shows the decoration at the 21st China (Shouguang) International Vegetable Science and Technology Expo in Shouguang, east China's Shandong Province. (Xinhua/Guo Xulei)

Photo taken on April 20, 2020 shows the decoration at the 21st China (Shouguang) International Vegetable Science and Technology Expo in Shouguang, east China's Shandong Province. (Xinhua/Guo Xulei)

Photo taken on April 20, 2020 shows the decoration at the 21st China (Shouguang) International Vegetable Science and Technology Expo in Shouguang, east China's Shandong Province. (Xinhua/Guo Xulei)

Photo taken on April 20, 2020 shows the decoration at the 21st China (Shouguang) International Vegetable Science and Technology Expo in Shouguang, east China's Shandong Province. (Xinhua/Guo Xulei)

Photo taken on April 20, 2020 shows the decoration at the 21st China (Shouguang) International Vegetable Science and Technology Expo in Shouguang, east China's Shandong Province. (Xinhua/Guo Xulei)

Photo taken on April 20, 2020 shows the decoration at the 21st China (Shouguang) International Vegetable Science and Technology Expo in Shouguang, east China's Shandong Province. (Xinhua/Guo Xulei)