This combination photo shows a view of the now-defunct Leal Senado (the local government under Portuguese colonial rule) in Macao (top, photo by Chen Demu, issued on Nov. 4, 1999), and a lion dance performance at the Senado Square in front of the Municipal Affairs Bureau in Macao, south China on Feb. 7, 2019 (bottom, photo by Cheong Kam Ka). On Dec. 20, Macao will celebrate the 20th anniversary of its return to motherland. Over the past two decades, the special administrative region has made great strides in economic development and achieved prosperity and stability under the "one country, two systems" principle. Since Dec. 20, 1999, the historic day for Macao, what has changed? And what remains unchanged? Our selection of photos present comparative illustrations of the south China city's past and present. (Xinhua)