Passengers queue at Qingdao Liuting International Airport in Qingdao, east China's Shandong Province, Feb. 21, 2018. Passenger numbers are expected to grow on Wednesday, the last day of week-long Chinese Lunar New Year holiday. (Xinhua/Li Ziheng)

Passengers queue at Qingdao Liuting International Airport in Qingdao, east China's Shandong Province, Feb. 21, 2018. Passenger numbers are expected to grow on Wednesday, the last day of week-long Chinese Lunar New Year holiday. (Xinhua/Li Ziheng)

Passengers queue and board the train at Guiyang Railway Station in Guiyang, capital of southwest China's Guizhou Province, Feb. 21, 2018. Passenger numbers are expected to grow on Wednesday, the last day of week-long Chinese Lunar New Year holiday. (Xinhua/Tao Liang)