A farmer works in a greenhouse at an agricultural garden in Luanzhou City, north China's Hebei Province, March 29, 2020. Photo:Xinhua

A farmer packs strawberries in a greenhouse at an agricultural garden in Luanzhou City, north China's Hebei Province, March 29, 2020.Photo:Xinhua

A farmer picks strawberries in a greenhouse at an agricultural garden in Luanzhou City, north China's Hebei Province, March 29, 2020.Photo:Xinhua

Farmers work in a seedling greenhouse at an agricultural garden in Luanzhou City, north China's Hebei Province, March 29, 2020.Photo:Xinhua