Tourists walk through an alley near the Ruins of St. Paul's in Macao, south China, Dec. 17, 2019. 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. Photo: Xinhua

 

Tourists visit the Ruins of St. Paul's in Macao, south China, Dec. 17, 2019. 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. Photo: Xinhua

 

China's national flags and flags of China's Macao Special Administrative Region (SAR) are seen along a road in Macao, south China, Dec. 17, 2019. 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. Photo: Xinhua

 

Women walk past a restaurant near the Fisherman's Wharf in Macao, south China, Dec. 17, 2019. 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. Photo: Xinhua

 

Women walk on a footbridge with baby strollers near the Macao Science Center in south China's Macao, Dec. 17, 2019. 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.Photo: Xinhua

 

People visit the Macao Museum in south China's Macao, Dec. 17, 2019. 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. Photo: Xinhua

 

Photo taken on Dec. 17, 2019 shows the scenery at sunrise in south China's Macao. 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. Photo: Xinhua

 

Photo taken on Dec. 17, 2019 shows the night view of Ruins of St. Paul's in Macao, south China. 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. Photo: Xinhua

 

Photo taken on Dec. 17, 2019 shows a view of the Ponte de Amizade (Bridge of Friendship) in south China's Macao. 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. Photo: Xinhua

 

A man takes photos at the Fisherman's Wharf in Macao, south China, Dec. 17, 2019. 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. Photo: Xinhua

 

A girl poses for photos near the Fisherman's Wharf in Macao, south China, Dec. 17, 2019. 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. Photo: Xinhua

 

A woman wearing a wedding dress poses for photos at the Fisherman's Wharf in Macao, south China, Dec. 17, 2019. 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. Photo: Xinhua

 

Freighters sail in the sea near the Ponte de Amizade (Bridge of Friendship) in south China's Macao, Dec. 17, 2019. 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. Photo: Xinhua