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    In what way do you think the sun cannot be harmful? A. The sun can do harm to your eyes and skin. B. It can make rivers too dry. C. Without it there would be no life on Earth. D. Hot sun on dry land can cause fires. Passage 12 Most animals only have animals of a different kind for food. But sometimes two kinds of animals come together in a partnership which is good for them. You may have noticed some birds on the backs of sheep. This is not because they want a ride, but because they find easy food in the parasites on sheep. The sheep let the birds do so because they can stop the parasites from troubling them. So though they can do with it by themselves, they can do better together with each other. Sometimes an animal has a plant partner. The relationship develops until the two partners cannot do without each other. This is so in corals of the sea. Inside their bodies they have very small plants, which act as “cleaners , taking the useless things from the coral and giving oxygen in return. That is what the animal needs to live. If the plants are killed, or are even kept from receiving light so that they cannot live as usual, the corals will die. 【查看更多】

     

    题目列表(包括答案和解析)

    阅读理解

    　　WHY IS THE SUN IMPORTANT?

    　　The sun is a huge, hot, bright star．It is important because without it there would be no life on Earth．The sun gives us light and heat．

    　　All living things need light and heat from the sun to live．Plants need light and heat to grow．They use the light from the sun to make food．We cannot make our own food, but plants can．All the food we eat comes from plants in a food chain(链)which starts with the sun．For example,

    　　Animals need sunlight, too．Just like us, their food comes from a food chain which begins with the sun and the plants．

    　　sun→ leaf→ caterpillar(毛虫)→bird

    　　sun→ seaweed(海藻)→small fish→ whale(鲸)

    　　Sunlight means we can see during the day．If there was no sun, it would be dark all the time．Even when the sky is cloudy, the sunlight is very strong and it shines through the clouds．

    (1)

    Which words tell us what the sun is like?

    [　　]

    A．

    Huge．

    B．

    Hot．

    C．

    Bright．

    D．

    All above．

    (2)

    What are the two main things the sun gives us?

    [　　]

    A．

    Light and heat．

    B．

    Heat and eggs．

    C．

    Corn and light．

    D．

    Wheat and bread．

    (3)

    Why can we still see during the day when the sky is cloudy?

    [　　]

    A．

    Because we can see all day and all night．

    B．

    Because the sun can't give us light all day long．

    C．

    Because the sunlight can shine through the clouds．

    D．

    Because we can't see at night．

    (4)

    All the food we eat comes from ________．And it starts with the ________．

    [　　]

    A．

    plants; earth

    B．

    a food chain; sun

    C．

    food; sun

    D．

    plants; star

    (5)

    In what way do you think the sun cannot be harmful(有害的)？

    [　　]

    A．

    The sun can do harm to your eyes and skin．

    B．

    It can make rivers too dry．

    C．

    Without it there would be no life on Earth．

    D．

    Hot sun on dry land can cause fires．

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