16. We don`t know how birds find their way home but we know … they will surely return again with the warmth and sunshine of spring.
A) ever B) because of C) that D) what
17. Last night I heard uncle Henry … something to Paul. To my astonishment, he seemed to be asked what had happened to me.
A) to be whispering B) whispering C) to whisper D) to have whispered
18. If it rains today, we … go out.
A) won`t B) wouldn`t C) aren`t D) doesn`t
19. San Marino is a small republic situated on the Adriatic side of … central Italy.
A) this B) – C) that D) a
20. Beethoven`s life and career were coloured by an unusual tragedy that gave him no … but to change and adjust. Some scholars believe that his deafness gave him freedom to experiment with new forms in music.
A) choose B) choice C) choosing D) chosen
Helicopters are very different from airplanes. They can do three things that airplanes cannot do. First, when airplanes move upward, they must also move forward, but helicopters can move straight up without moving ahead. Second, helicopters can fly backward, which airplanes cannot do. Third, helicopters can use their rotors to hover in the air which is impossible for planes. Because they can perform action that airplanes cannot, they are used for different tasks. Since helicopters can take off without moving forward. They do not need a runway for taking off. They are used in congested areas where there is no room for airplanes or in isolated areas which do not have airports. Because they can hover, they are used on firefighting missions to drop water on fires. They are used in logging operations to lift trees out of forest. Helicopters are as air ambulances to airlift patients out of situations which are difficult to reach by conventional ambulances. The police use helicopters to follow suspects on the ground or to search for cars on the ground. Of course, helicopters have military uses because their design and capabilities.
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