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Nowadays almost every city has an airport,【C1】______two, in the ease of some big cities. Like a railway station, an airport is a very【C2】______place. At almost any hour of the day or night it is thronged【C3】______people, many of them are passengers who are【C4】______waiting for a flight out or who have just【C5】______. Today, a great number of people travel from one country to another by plane just as【C6】______as other people【C7】______from one town to another within the same country by train or bus.
The big building in which passengers wait for their plane is called the【C8】______. When a passenger arrives【C9】______the terminal, he goes to the airline【C10】______has arranged his trip. There he【C11】______his ticket as【C12】______that he has a seat in the plane. He also【C13】______his heavy luggage to【C14】______and sent to the hold of the aircraft. The passenger is allowed to carry only light articles with him. If his ticket is in order, and his luggage is not【C15】______, he is given a card called a【C16】______pass which allows his admission【C17】______the plane. However, he can not proceed to the aircraft【C18】______he【C19】______an announcement over the loudspeakers that his plane is about to【C20】______.
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【C1】

A. only
B. even
C. lastly
D. ever