Top: File photo taken in 1965 shows oil workers taking out a long rock core for the first time in Daqing, northeast China's Heilongjiang Province. Bottom: Photo taken on June 26, 2019 by Wang Jianwei shows Jiang Hongwei of No. 1202 drilling team introducing an advanced drill in use at Daqing Oilfield. Nowadays, workers can realize fast and efficient operation in drilling control rooms with the upgrade of mechanization and automation level. In 1949 when the People's Republic of China was founded, the Chinese people faced a devastated country that needed to be rebuilt from scratch after decades of warfare and chaos. After decades of unremitting endeavors and dedication by the Chinese people, China has grown to be the world's second largest economy. In 1952, China's GDP was 30 billion U.S. dollars, while in 2018, its GDP reached 13.61 trillion U.S. dollars, an increase of 452.6 times. A group of combo photos give you a glimpse of what Chinese people did decades ago and what they do right now. Undoubtedly, people from all walks of life in China with hard work and wisdom have made contributions to the country's development. (Xinhua)