A. Airport services
B. Air transport prices
C. Transport by plane
D. Development
E. Fast growth in the US airlines
F. Beginning time
　　　　　 
Airplanes are used to carry passengers, cargo and mail. Air transport companies run scheduled airlines and non-scheduled services over local, national, and international routes. The aircraft run by these companies change from small planes to large planes.
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The first air passenger services began in 1910, when dirigibles(飞艇)began working between several German cities. The first scheduled airplane service to carry passengers began in the US in 1914. Several experimental airmail flights took place in India, Europe, and the USA before World War I, but air transport services did not become a true business until after the war.
　　　　　 
During World WarⅡintercontinental air transport began to become well set-up. After the war the new long-distance planes with developed equipment were increasingly able to prevent storms and strong wind and make flights cheap. Jumbo Jets began working in 1970.
　　　　　 
During the 1970s the number of home passengers on US airlines increased about 78%, and during the 1980s the number was up about 58%. In 1990 there were 41. 8 million international passengers: the number was a 75% increase over 1980.
　　　　　 
Major airports provide all kinds of services to make travel easy and pleasant for passengers. These change from such basic services as ticket-sales counters and restaurants to luxury(豪华的)hotels, shopping centers and play areas for children.