A medical worker takes care of a patient at a hospital in Danzhai County of Qiandongnan Miao and Dong Autonomous Prefecture, southwest China's Guizhou Province, May 1, 2020. People from various sectors stick to their posts during the Labor Day holiday. (Photo by Yang Wukui/Xinhua)

A person works at a greenhouse in Tancheng County of Linyi City, east China's Shandong Province, May 1, 2020. People from various sectors stick to their posts during the Labor Day holiday. (Photo by Zhang Chunlei/Xinhua)

People work at a highway construction site in Pingyi County of Linyi City, east China's Shandong Province, May 1, 2020. People from various sectors stick to their posts during the Labor Day holiday. (Photo by Wu Jiquan/Xinhua)

Conductor Zhou Huiyu prepares for departure on the G77 train in Wuhan, central China's Hubei Province, May 1, 2020. People from various sectors stick to their posts during the Labor Day holiday. (Photo by Zhao Jun/Xinhua)

A staff member works at a textile company in Yiyuan County of Zibo, east China's Shandong Province, May 1, 2020. People from various sectors stick to their posts during the Labor Day holiday. (Photo by Zhao Dongshan/Xinhua)

Workers check equipment in Lianyungang City, east China's Jiangsu Province, May 1, 2020. People from various sectors stick to their posts during the Labor Day holiday. (Photo by Zhu Hua'nan/Xinhua)

A worker is seen at the workshop of Liaoning Fu-An Heavy Industry Co., Ltd. in Anshan, northeast China's Liaoning Province, May 1, 2020. People from various sectors stick to their posts during the International Labor Day holiday. (Xinhua/Yao Jianfeng)

A sanitation worker cleans up a street in Fuzhou, southeast China's Fujian Province, May 1, 2020. People from various sectors stick to their posts during the International Labor Day holiday. (Xinhua/Lin Shanchuan)