题目内容
阅读理解
Some scientists think that one day animals may be trained to do a number of simple jobs that are now done by human beings. They pointed out that at a circus (马戏团), for example, we may see elephants, monkeys, dogs and other animals doing quite skillful things. If you watch closely, you may notice that the trainer always gives the animals a lump(块) of sugar or a piece of fruit as a reward(报酬).
In Russia, for example, pigeons, which are birds with good eyesight, are being used to watch out for faults in small steel balls that are being made in a factory. When the pigeon sees a ball which looks different from the other, it touches a steel plate with its beak(鸟嘴). This turns on a light to warn the people in the factory. At the same time a few seeds are given to the pigeon as a reward. It takes three or five weeks to train a pigeon to do this and one pigeon can check 3 000 to 4 000 balls an hour.
1.Which of these words is nearer in meaning to “trained” in the passage?
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2.The trainer gives an animal a piece of sugar or fruit ________.
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A.when the animal is hungry
B.to make the animal do something
C.after the animal have done the trick
D.before the animal is going to do the trick.
3.Pigeons are used to examine the small steel balls because ________.
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A.they are clever birds
C.they have beaks
B.they can see well
D.they can tell us the number
4.The pigeon touches the plate with its beak when ________.
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