Top: File photo taken in 1977 by Fan Mingtao shows Lu Lilian from Zhengzhou Railway Bureau patrolling the railway line at night. Bottom: Photo taken on Jan. 21, 2019 by Li An shows rail flaw detectors from the Zhengzhou section of China Railway Zhengzhou Group Co., Ltd. on the way for work. Instead of adopting simple methods like observing and striking rails with a hammer to detect rail flaws in the past, railway workers now carry out flaw detection with advanced equipment, such as rail flaw detection vehicles to inspect and eliminate potential rail safety hazards. 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)