Photo taken on May 29, 2018 shows Zhang Lianlian helping a seedling up in Leipingta Village, Yan'an City of northwest China's Shaanxi Province. Friday marks China's National Tree Planting Day. With the efforts of volunteers across the country, green lands has covered more areas of China and the eco-friendly development concept is seeded in people's heart. (Xinhua/Shao Rui)
