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        Training?。粒睿椋恚幔欤?/h1>
        2008-12-26 09:11:28
        中學(xué)科技 2008年12期

        People realize that, although animals may not have the same intelligence as human beings, they are smart enough to learn certain things.

        Dogs are extremely useful as companions for blind people. When a dog has been properly trained, it will always lead its blind master in the right direction and keep him out of danger. For example, seeing-eye dogs learn never to cross a busy road when cars are coming, even if their masters command them to do so.

        Horses are also to learn many things. Horses that are used for guard or police duty must learn never to be frightened of noises, traffic, and other disturbances. Racing horses are able to run much faster than other horses, but they are also quite high strung. Therefore, it is necessary for those people who train them to be very patient and understanding.

        The moving pictures and television can use trained animals too. Some animals, such as monkeys and foxes, are easy to film. All you have to do is make a trail in front of the camera by dragging something that smells good to the animals over the ground. Big animals, such as lions and tigers, can be photographed as they bound happily back to their families and dinner. If a movie actor is nearby, the well-trained animal will pay no attention to him. However, the audience may imagine that the actor escaped a terrible death by the skin of his teeth.

        1. Dogs who help blind people must learn _______.

        A. to obey all orders B. to obey only safe orders

        C. never to cross busy roads

        D. tocross roadswhen com-

        manded to do so

        2. Racing horses are hard to train because they are _______.

        A. faster than other horses B. smaller than other horses

        C. clever than other horses

        D. morenervousthanother horses

        3. What does “make a trail” mean here in the last paragraph?

        A. place something to attract the animal.

        B. give the animal a certain task C. order the animal to do things

        D. follow the animal to hunt

        4. Lions can be photographed easily when _______.

        A. they are following a trail of something that smells good to them

        B. they are returning to their families

        C. they have been trained to work with other animals

        D. they do not know a movie-actor is nearby

        Sharks Perform a Service for Earth's Waters

        It is hard to get people to think of sharks as anything but a deadly enemy. They are thought to attack people frequently. But these fish perform a valuable service for earth's waters and for human beings. Yet business and sport fishing are threatening their (A) e_______ . Some sharks are at risk of disappearing from Earth.

        Warm (1) w_______ may influence both fish and sharks activities. Many fish swim near coastal areas because of their warm waters. Experts say sharks may follow the fish into the same areas, where people also swim.In fact, most sharks do not purposely bite humans. They are thought to (B) m_______ a person for a sea animal, like a seal or sea lion. That is why people should not swim in the ocean when the sun goes down or comes up. Those are the times when sharks are looking for food. Experts also say that bright colors and shiny (C) j_______may cause sharks to attack.

        Sharks have extremely good senses of smell. They can find small (D) a_______ of substances in water, such as blood, body liquids and chemicals produced by animals. These powerful senses help sharks find their food. Sharks eat fish, other sharks, and plants that live in the ocean.

        Medical researchers want to learn more about the shark's body defense system against (2) d_______. Researchers know that sharks recover quickly from injuries. They study sharks in hopes of finding a way to fight human disease.

        Sharks are (3) i_____for the world's oceans. They eat injured and diseased fish. Their hunting activities mean that the numbers of other fish in ocean waters do not become too great. This (4) p ______the plants and other forms of life that exist in the oceans.

        (A, B, C, D FOR CROSS, 1, 2, 3, 4 FOR DOWN. The first letters of the absents were given)

        Hungry Scientists (2)

        The four scientists sit at a round table. Determine each scientists field based on the clues below.

        (1) Susan sits across from the biologist.

        (2) Fred sits to the right of the chemist.

        (3) ThegeologistandFred are both short.

        (4) Thegeologistandthe physicistsitoppositeeach other.

        (5) Maxandthegeologist both practice tae kwon do.

        上期Crossword答案

        1. research 2. extremely

        3. physiology 4. associated

        5. function 6. survival

        A. disordersB. decline

        C. affectD. precious

        上期Illation答案

        Max Tissue, Charles Osmium, Fred Radian, Susan Infinity

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