Liu Hongsheng (R), associate chief physician of thoracic surgery department, and his wife Ni Jun, chief physician of neurology department, pose for a photo at their work place of the Peking Union Medical College Hospital in Beijing, capital of China, Aug. 16, 2019. China has about 3.6 million qualified physicians and 4.1 million registered nurses. They have formed a strong force to support the most significant medical service system in the world of safeguarding the health of 1.4 billion people in the country. China designated Aug. 19 as Medical Workers' Day last year to call for respect from society for the country's medical and health workers. During this year's Medical Workers' Day, photographers of China's Xinhua News Agency focus with their lens on 11 pairs of physician couples, both of whom work at the same hospital, in different ages. (Xinhua/Zhang Yuwei)