Workers debug devices at the terminal building of Beijing Daxing International Airport in Beijing, capital of China, June 19, 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 Sept. 30. (Photo: China News Service/Yin Liqin)

Workers debug devices at the terminal building of Beijing Daxing International Airport in Beijing, capital of China, June 19, 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 Sept. 30. (Photo: China News Service/Yin Liqin)

Workers debug devices at the terminal building of Beijing Daxing International Airport in Beijing, capital of China, June 19, 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 Sept. 30. (Photo: China News Service/Yin Liqin)

Workers debug devices at the terminal building of Beijing Daxing International Airport in Beijing, capital of China, June 19, 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 Sept. 30. (Photo: China News Service/Yin Liqin)

People work at the construction site of Chinese Garden 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 Sept. 30. (Photo: China News Service/Yin Liqin)

Workers debug devices at the terminal building of Beijing Daxing International Airport in Beijing, capital of China, June 19, 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 Sept. 30. (Photo: China News Service/Yin Liqin)

People work at the construction site of Chinese Garden 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 Sept. 30. (Photo: China News Service/Yin Liqin)