Photo taken on June 18, 2019 shows the terminal building of Beijing Daxing International Airport in Beijing, capital of China. The construction of the Beijing Daxing International Airport is expected to be completed by the end of this month. The new airport is scheduled to be put into operation before September 30. (Photo: Xinhua)

People work at the construction site of the terminal building at Beijing Daxing International Airport in Beijing, capital of China, June 18, 2019. The construction of the Beijing Daxing International Airport is expected to be completed by the end of this month. The new airport is scheduled to be put into operation before September 30. (Photo: Xinhua)

Photo taken on June 18, 2019 shows the terminal building of Beijing Daxing International Airport in Beijing, capital of China. The construction of the Beijing Daxing International Airport is expected to be completed by the end of this month. The new airport is scheduled to be put into operation before September 30. (Photo: Xinhua)

Workers install and debug devices at the terminal building of Beijing Daxing International Airport in Beijing, capital of China, June 18, 2019. The construction of the Beijing Daxing International Airport is expected to be completed by the end of this month. The new airport is scheduled to be put into operation before September 30. (Photo: Xinhua)

Workers are seen at the terminal building of Beijing Daxing International Airport in Beijing, capital of China, June 18, 2019. The construction of the Beijing Daxing International Airport is expected to be completed by the end of this month. The new airport is scheduled to be put into operation before September 30. (Photo: Xinhua)

Photo taken on June 18, 2019 shows the terminal building of Beijing Daxing International Airport in Beijing, capital of China. The construction of the Beijing Daxing International Airport is expected to be completed by the end of this month. The new airport is scheduled to be put into operation before September 30. (Photo: Xinhua)

Photo taken on June 18, 2019 shows the terminal building of Beijing Daxing International Airport in Beijing, capital of China. The construction of the Beijing Daxing International Airport is expected to be completed by the end of this month. The new airport is scheduled to be put into operation before September 30. (Photo: Xinhua)