Điền từ giúp tui với:

Air travel is ___ most modern form of public  transport and it was developed in the 20^th century. Millions of people use airplanes ___ a variety of reasons. It is also extremely expensive to ___ up air-travel facilities. Some travel for business, ____ go on holiday by air and others use cargo planes to move their products from country to _____ very quickly. Some courier companies now have their own fleet of planes ready to carry parcels and post more efficiently. There are different ____ of passenger services – some are cheap and provide a ‘no-frills’ service which is good for short journeys. Other airlines provide ____ with a luxurious flying experience. Airports ____ getting busier and it is evident ____ more passengers and businesses ____ ever are using airplanes to get to their destinations.