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　　Here is an interesting experiment. Hold a postcard in your left hand. your right hand is ready to catch the postcard, but the fingers are not touching it. If you let the postcard go, you’ll catch it without difficulty with your right hand before it falls down. If you haven’t got a postcard, you can use something like that instead. It can work well, too.

　　Now see if your classmate can catch the postcard when you let it go. Let your classmate hold his fingers Oil each side of the postcard, as you did before. Let the postcard go. His fingers will not catch it. You can try this as often as you want. He will not catch the postcard!

1．The passage is about ________.

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2．If you let the postcard in your left hand go, you’ll find it ________ to catch it before it falls down.

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3．Let your classmate do this as you did before, he will surely ________.

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4．If we haven’t got a postcard we can use ________ instead.

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A．something like a postcard

B．something to do with a postcard

C．everything to see

D．anything we can find

5．We can learn something about ________ from the passage.

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　　Besides（除了）the cold and darkness, deep-sea animals face a third danger－other animals.

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A．they want to catch fish

B．they want to find the secrets of the undersea world

C．the sea is deep

D．there are all kinds of plants in the sea

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A．can see everything green and blue

B．can't be in danger

C．can catch nothing

D．can't see anything clearly

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A．stay in deep water for a long time

B．dive very, very deep

C．live in deep water easily

D．dive freely without any dangers

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A．One animal finds something to eat, and it may be eaten by others.

B．At the depth of 3,000 feet under the sea, many animals can find their way by hearing and feeling.

C．The deeper the sea is, the darker and colder it is.

D．At the depth of 3,000 feet under the sea, all animals can find their way by seeing.

The undersea world is very beautiful ,.Now more and more people want to dive in the water to find the secret there . Scuba diving is a new sport today. It can take you into a wonderful undersea world.

You will find many strange animals in the sea. Some are as large as a school bus. Many sea animals give out light in the dark and some have sharp teeth.

During the day , there is enough light . Here , under the sea , everything is blue and green .

When fish swim nearby, you can catch them with your hands. When you have bottles of air on your back, you can stay in deep water for a long time. However , you can’t dive too deep . And you must be very careful when you dive in deep water .

The deep sea is not an easy place to live in . It’s cold, and it’s dark, too. The deeper it is , the less sunlight there is . About 3 000 feet , there is no light at all . It is very dark in the sea. Many fishes have no eyes . Some have big eyes . A few have eyes on one side .

Besides (除了) the cold and the darkness , deep-sea animals face a third danger ---other animals . Animals eat ! They must find food to eat . Many animals eat plants . However , some animals eat meat . This means these sea animals have two big jobs . They need to find animals as food, and they have to try not to become other animals’ meal.

（  ）6. Why do people want to dive in the sea ? Because                .

  A. they want to catch fish     B. they want to find the secrets of the undersea world

  C. the sea is deep            D. there are all kinds of plants in the sea

（  ）7. In the daytime , when you dive in the sea, you                .

  A. can sea everything green and blue    B. can’t be in danger

  C. can catch nothing                 D. can’t see anything clearly

（  ）8. How many dangers will animals meet in the deep sea ?

  A. One           B. Two          C. Three           D. Four

（  ）9. When you do scuba diving , you can           .

  A. stay in deep water for a long time       B. dive very , very deep

  C. live in deep water easily               D. dive freely without any danger

（  ）10. Which of the following is WRONG ?

  A. One animal finds something to eat , and it may be eaten by others .

  B. At the depth of 3 000 feet under the sea , many animals can find their way by bearing and feeling .      C. The deeper the sea is , the darker and colder it is .

D. At the depth of 3 000 feet under the, all animals can find their way by seeing