Kids take a lesson as a kindergarten reopens in Jinan, east China's Shandong Province, June 8, 2020. Kindergartens in Jinan reopened on Monday under COVID-19 prevention and control measures. (Xinhua/Wang Kai)

Kids take a lesson as a kindergarten reopens in Jinan, east China's Shandong Province, June 8, 2020. Kindergartens in Jinan reopened on Monday under COVID-19 prevention and control measures. (Xinhua/Wang Kai)

Kids enter a kindergarten reopens in Jinan, east China's Shandong Province, June 8, 2020. Kindergartens in Jinan reopened on Monday under COVID-19 prevention and control measures. (Xinhua/Wang Kai)

Kids take a lesson as a kindergarten reopens in Jinan, east China's Shandong Province, June 8, 2020. Kindergartens in Jinan reopened on Monday under COVID-19 prevention and control measures. (Xinhua/Wang Kai)

Kids take a lesson as a kindergarten reopens in Jinan, east China's Shandong Province, June 8, 2020. Kindergartens in Jinan reopened on Monday under COVID-19 prevention and control measures. (Xinhua/Wang Kai)

Kids take a lesson as a kindergarten reopens in Jinan, east China's Shandong Province, June 8, 2020. Kindergartens in Jinan reopened on Monday under COVID-19 prevention and control measures. (Xinhua/Wang Kai)

A kid gets his temperature measured before entering a classroom at a kindergarten in Jinan, east China's Shandong Province, June 8, 2020. Kindergartens in Jinan reopened on Monday under COVID-19 prevention and control measures. (Xinhua/Wang Kai)

Kids take a lesson as a kindergarten reopens in Jinan, east China's Shandong Province, June 8, 2020. Kindergartens in Jinan reopened on Monday under COVID-19 prevention and control measures. (Xinhua/Wang Kai)