第3章 实战演练
阅读理解材料浩如烟海，中考英语复习，时间短，任务重。为了能让同学们脱离题海，更加省时省力地提高自己的阅读理解能力，我们特意选编了一些题材新颖、质量上乘的阅读材料。这些材料内容丰富，趣味性强，无论是在设计上，还是在难度上，都与中考英语试题相当。“会当凌绝顶，一览众山小”。完成这些短文及题目之后，再做中考阅读理解题，就一定能驾轻就熟，游刃有余。
Section I 缤纷自然篇
Passage 1
We know that many animals do not stay in one place. Birds, fish and other animals move from one place to another at a certain time. They move for different reasons: most of them move to find food more easily, but others move to get away from places that are too crowded.
When cold weather comes, many birds move to warmer places to find food. Some fishes give birth in warm water and move to cold water to feed. The most famous migration (迁移) is probably the migration of fish, which is called “salmon”. This fish is born in fresh water but it travels many miles to salt water. There it spends its life. When it is old, it returns to its birthplace in fresh water. Then it gives birth and dies. In northern Europe, there is a kind of mouse. They leave their mountain homes when they become too crowded. They move down to the low land. Sometimes they move all the way to the seaside, and many of them are killed when they fall into the sea.
Recently (近来), scientists have studied the migration of a kind of lobster (龙虾). Every year,
when the season of the bad weather arrives, the lobsters get into a long line and start to walk
across the floor of the ocean. Nobody knows why they do this, and nobody knows where they go.
So, sometimes we know why humans and animals move from one place to another, but at other
times we don’t. Maybe living things just like to travel.
1.Most animals move from one place to another at a certain time to _______.
A.give birth B. enjoy warmer weather
C. find food more easily D. find beautiful places
2.The fish called “salmon” spends a long time in ______.
A. salt water B. rivers C. fresh water D. its birthplace
3.The mice in northern Europe move when _______.
A. they give birth B. the place gets too crowded
C. the weather is bad D. they haven’t enough food
4.The lobsters move ________.
A. to the fresh water B. at a certain time C. to the undersea D. to find more food
5.What is the main idea of the passage?
A.Animals move to find food more easily.
B.The migration of the fish called “salmon” is the most famous migration.
C.Living things move from one place to another because they like to travel.
D. Sometimes we know why and how living things move from one place to another, but sometimes we don’t.
Passage 2
If you look at the sky one night and see something moving and shining that you have never seen before, it might be a comet (彗星).
A comet sometimes looks like a star. Like a planet, a comet has no light of its own. It shines from the sunlight it reflects (反射). Like the earth, a comet goes round the sun, but on a much longer path (轨道) than the earth travels.
If a comet isn’t a star, what is it then?
Some scientists think that a large part of a comet is water frozen into pieces of ice and mixed with iron and rock dust and perhaps a few big pieces of rock. When sunshine melts (融化) the ice in the comet, great clouds of gas go trailing after it. These clouds, together with the dust, form a long tail.
Many people perhaps have seen a comet. However no one knows how many comets there are. There may be millions of comets, but only a few come close enough for us to see.
An Englishman named Edmund Halley, who lived from 1656 to 1742, found out a lot about the paths that comets take through the sky. Some comets move out of our sight and never come back. Others keep coming back at regular times. A big comet that keeps coming back was named after Halley because he was the one who worked out when it would come back again. Maybe you have ever seen Halley’s Comets because the last time it came close to the sun and the earth was in the year 1986. Then people all over the world were outside at night to look at it. You will probably be able to see Halley’s Comets when it comes near the earth again.
1.A comet is like ________.
A. sun B. moon C. sunlight D. the earth
2.A large part of a comet is ______.
A.water and rock B. water frozen into pieces of ice and mixed with iron
C. ice, iron and rock dust D. only a few big pieces of rock
3.Maybe many people _______.
A. haven’t seen any comets B. have seen all comets
C. have seen a comet at daytime D. have seen a comet
4.Some comets keep coming back ________.
A. at any time B. at noon C. at regular times D. at daytime
5.Halley’s Comets came back _____.
A. in 1990 B. in 1980 C. in 1986 D. in 1989
Passage 3
Do you know something about tree rings (年轮)? Do you know they can tell us what the weather was like, sometimes even hundreds of years ago?
A tree will grow well in a climate (气候)with lots of sunshine and rainfall. And little sunshine or rainfall will limit (限制)the growth of climate by studying the tree rings. For example, to find out the weather of ten years ago, count the rings of a tree from the outside to the inside. If the tenth ring is far from the eleventh ring, then we’re sure that it was sunny and rainy most of that year. If it is near to the eleventh ring, then the climate that year was bad.
Tree rings are important not only for studying the history of weather but also for studying the history of man. Many centuries ago there lived a lot of people at a place in New Mexico. But now you can find only sand there—no trees and no people. What happened?
A scientist studied the rings of dead trees there. He found that the people had to leave because they had cut down all the trees to make fires and buildings. As all the trees had gone, the people there had to move.
1._____ in good climate.
A. Tree rings grow far from each other B. Tree rings become thinner
C. Trees don’t need sunshine or rainfall D. People can cut down most of the trees
2.The scientists are interested in studying tree rings because tree rings can tell ______.
A.whether a tree was strong or not B. whether people took good care of the trees or not
C. whether the climate was good or not D. how old the trees were
3.If you want to find out the weather of twenty years ago, you should study _______.
A. the twentieth ring B. the tenth ring
C. the nineteenth ring D. the twenty-first ring
4.Why did people usually live in places with lots of trees?
A.Trees could tell the change of the weather
B.Trees brought lots of sunshine and rain
C.Trees could make weather not too hot or too cold
D.Trees could be used for burning and for building house
5.The people had to leave the place in New Mexico because _______.
A.had weather stopped the growth of trees
B.they no longer had water and the land became sand
C.they didn’t have enough trees for burning
D.there was too much rain there
Passage 4
All our food comes from the soil (土壤). Some of us eat meat, but animals live on plants. If these were no plants, we should have no animals and meat. So the soil is necessary for life.
The top of ground is usually covered with grass or other plants. Plants grow in soil, which has a dark color. This dark soil is humus, dead leaves, dead plants and animal waste make it, but this takes a long time. When the humus has been made, plants can grow well in it.
All soil needs food. If we don’t give it any, the plants will be weak. Animals waste is the best food for the soil, but chemical fertilizers (化肥) are also very useful. The same crop should not be grown in the same place every year; it is better to have a different crop. A change of crop and the use of a good fertilizer will keep the land in good condition.
When the soil is dry, the wind blows it away. Sometimes heavy rain carries the humus down to a river. People should grow more and more trees and grass to stop wind from carrying the humus away. It takes hundreds of years to make humus, and so we must save every bit of it. Without soil, where can we grow food?
1.From the text, we know people live on _______.
A. animal B. plant C. meat D. soil
2.The word “humus” means _____ in Chinese.
A.微生物 B.土壤 C.腐殖土 D.粘土
3.We should _______ to keep the soil.
A. give more fertilizers B. kill more animals
C. make more humus D. grow more trees and grass
4.We should save every bit of humus, because ______.
A.it takes a long time to make humus
B.the more humus in the soil, the better plants grow
C.the chemical fertilizers are expensive
D.A and B
5.The best title of this text should be ______.
A.Soil is necessary to people
B.The same crop can’t be grown in the same place every year
C.Soil’s food is chemical fertilizers
D.Humus is hard to make
Passage 5
In the sea there are many islands. In its warm waters there are some little ones. We call them “coral Islands”.
A coral island is very nice to look at. It looks like a ring of land (一圈陆地) with trees, grass, and flowers on it. One part of the ring is open to the water. There is a little round lake inside the island.
If you look into this lake, you will see beautiful coral. You say think they are flowers. If you look at a piece of coral, you will see many little holes in it. In each of these holes a very small sea animal has lived. These sea animals make the coral.
They began to build under the water. Year after year, the coral grew higher and higher. At last it grew out of the water.
Then the sea brought it small trees and something else. After some years, these things changed into earth. Sometimes the wind brought seeds (种子) to this earth. Sometimes birds flew over it and brought seeds to the island.
The little seeds grew. In a few years there were plants all over the island. In a few more years there were trees growing there.
So you see, these islands were built little by little. The workers were very small. Do they not teach us a lesson? Can you think what the lesson is?
1.In the sea ________.
A. there are coral islands in all places B. there are some coral islands
C. the water is always warm D. we can see many flowers
2.A coral island looks like __________.
A. a round cake B. trees, grass and flowers
C. a ring of land D. a round lake
3.There are _______ in the holes in corals.
A. flowers B. little corals C. grass D. sea animals
4.How did seeds of trees, grass and flowers come to the coral islands? ________
A.The wind and birds brought them to the coral islands
B.Only the wind brought them there
C.People brought them there
D.Fishes brought them there
5.From the story we learn that ___________.
A.small workers can’t do big things
B.only big workers can do big things
C.small workers can do big things if they work hard work and work a long time
D.all small things can do big things
Passage 6
When some plates of the earth move suddenly, an earthquake happens. Many earthquakes begin under the sea. Earthquakes may happen anywhere on the earth. They often happen near the mountains.
During an earthquake, the shakings make rocks rise suddenly and even crack (断裂) open. Houses fall, people are killed or hurt, and sometimes the whole villages or cities are destroyed.
Can we do something to keep ourselves safe from earthquakes? Scientists have studied earthquakes and make maps that show the “earthquake belts”. In areas (地区) in these belts, it’s possible for earthquakes to happen. In these areas we should build strong houses to fight against earthquakes.
In the future, scientists will be able to tell when and where an earthquake will be before they happen. They can also tell people what to do and how to do it.
1.A large number of earthquakes often happens ________.
A. in the area B. on land C. at night D. next to mountains
2.The reason for an earthquake is _______.
A.the result of rock plate sudden movement
B.that there are so many plates on the earth
C.that the sea is too deep
D.rocks’ cracking open
3.A map showing the earthquake belts will tell people ______.
A.what kind of houses to build
B.what kind of houses can stay up in an earthquake
C.where earthquake may happen
D.how to keep themselves safe during an earthquake
4.In the future we’ll be no longer so afraid of earthquakes ______.
A.with the help of scientists’ exact prediction (预报)
B.because of a map showing the “earthquake belts”
C.because we can guess the date and place of earthquakes
D.as scientists know what to do and how to do it
5.Choose the best title fro the passage.
A.An Earthquake B. A Scientist and an Earthquake
C. How to Fight Against Earthquake D. Earthquakes Today and Tomorrow
Passage 7
It seems to us that the earth stands quite still (静止的). But it is really moving all the time. It turns around a make-believe line through its center. We call this make-believe line the earth’s axis (地轴). The two ends of the earth’s axis are called its poles (极). The earth travels twenty-four hours around its axis once.
We look at the sun and say it “travels” across the sky, but the sun doesn’t really do so. The turning of the earth makes us feel as if the sun were moving across the sky. We can’t see that the earth is moving because everything else on the earth is turning with us. As the earth turns around every twenty-four hours, first one half faces the sun and then the other half. When our half of the earth is facing the sun, we say it is “day”. When our half is away from the sun, we say it is “night”. It is the turning of the earth that tells us when to go to bed and when to get up.
1.The meaning of “a make-believe line” is “a line that ______”.
A. is called pole B. we can’t see
C. anyone can see D. we can make and believe
2.It takes the earth ______ to turn around its axis once.
A. a week B. a month C. 12 hours D. 24 hours
3.Usually we say, “The sun rises in the east and sets in the west.” In fact, the sun _______.
A. does not move B. is moving all the time
C. moves sometimes D. is too heavy to move
4.We can’t see the earth moving because _________.
A. the earth stands still B. everything on the earth is moving with us
C. the earth is smaller than the sun D. the earth goes only at night
5.When our part of the earth turns away from the sun we have “______”, and when our part faces the sun we have “_____”.
A.day; night B. day; day C. night; day D. night; night
Passage 8
We know the mosquito very well. Mosquitoes fly everywhere. They can be found almost all over the world, and there are more than 2,500 kinds of them.
No one likes the mosquito. But the mosquito may decide that she loves you. She? Yes, she. It’s true that male mosquito doesn’t bite (咬)and only the female mosquito bites because she needs blood to lay eggs. She is always looking for things or people she wants to bite. If she likes what she finds, she bites. But if she doesn’t like your blood, she will turn to someone else for more delicious blood. Next time a mosquito bites you, just remember you are chosen. You’re different from the others!
If the mosquito likes you, she lands on your body without letting you know. She bites you so quickly and quietly that you may not feel anything different. After she bites, you will have an itch (痒) on your body because she puts something from her mouth together with your blood. By the time the itching begins, and she has flown away.
And then what happens? Well, after her delicious dinner, the mosquito feels tired. She just wants to find a place to have a good rest. There, on a leaf or a wall, she begins to lay eggs, hundreds of eggs.
1.“Mosquito” means _______ in Chinese.
A.苍蝇 B.蜻蜓 C. 跳蚤 D.蚊子
2.We know mosquitoes very well because ___________.
A. they can be found easily B. they fly here and there
C. there are many kinds of them D. they can fly
3.If the mosquito doesn’t bite you, it will ________.
A. get angry with you B. be afraid of you
C. make a lot of noise D. choose another one
4.The mosquito bites you _________.
A. when you’re asleep B. because you have choose it
C. too quickly to let you know D. but doesn’t like you
5.Which of the following sentences is wrong?
A. The itching begins after the mosquito bites you . B. You feel terrible when the mosquito bites you.
C. Mosquitoes use blood to lay eggs. D. All the mosquitoes don’t like to bite people for blood.
Passage 9
We’ve talked about snails (蜗牛) and their slow move. But much of the time snails don’t move at all. They are in their shells (壳) —sleeping.
Hot sun will dry out a snail’s body. So at the least sign of hot sun, a snail draws its body into his shell. A snail will die in a heavy rain. So when it rains, a snail does the same thing, too. A snail can sleep for as long as it needs to. It spends all the winter months in its shell, asleep.
In the spring the snail wakes up. Its body, about three inches long, comes out from the shell. When hungry, the snail looks for food. Its eyes, at the end of the top feelers (触角), are very weak. But its sense (感觉) of smell is very strong. It helps the snail to find food and the new greens.
A snail’s mouth is no bigger than the point of a pin (大头针). Yet it has 256,000 teeth! The teeth are very small, and you can’t see them. If you put a snail in a hard paper box, it will eat its way out! And if a snail wears out its teeth, it will grow new ones.
1.A snail _________.
A.moves more slowly at night B.has thousands of feet
C.doesn’t move at all D.sleeps much of the time
2.In the sentence “A snail draws its body into its shell”, the word “draw” means _____.
A. to make with a pencil B. to push C. to pull D. to move away
3.From the story, we know _________.
A. a snail’s shell is very thin B. a snail can’t see well
C. a snail’s nose is quite short D. a snail’s body changes in different seasons
4.A snail goes to sleep when _____.
A. it feels hungry B. it is put into a paper box
C. spring is coming D. it rains heavily
5.Which of the following is wrong?
A.In winter the snail doesn’t eat or move. B.A snail doesn’t like living under the sun.
C.The snail’s teeth can’t be worn out. D.The snail’s nose helps to find food.
Passage 10
Jupiter’s Moons and How They Travel
The many moons of Jupiter travel around the planet in different directions (方向).
Jupiter is the largest planet in our solar system. Over the years, scientists have found that Jupiter has its own small solar system. Earth has one moon. Jupiter has at least sixteen and probably more.
Since there are so many moons, scientists began to number them. The numerals(numbers)tell the sequence, or order, in which the moons were found. They were slower to name the moons. All of Jupiter’s moons now have a name as well as a number.
The first five moons to be discovered are known as the “inner moons”. But they are not the closest to the planet. The closest is only 127,600 kilometers away from Jupiter. All the inner moons circle the planet in counter-clockwise direction, that is, opposite of the hands of a clock.
Jupiter’s middle group of moons are at least 11,100,000 kilometers from the planet. They also move in a counter-clockwise motion (moving). The four farthest moons are at least 20,700,000 kilometers away. These are called “outer moons”. They circle in a clockwise motion.
How many more moons do you think will be discovered？
1.What does “solar system” in this article mean？______
A. 银河系 B. 宇宙空间 C. 流星雨 D. 太阳系
2.Things that travel in the same direction as the hands of a clock are said to be traveling in a______.
A. clockwise direction B. counter-clockwise direction
C. same direction D. different direction
3.Jupiter’s _____group of moons travel in a clockwise direction.
A. planets B. inner C. middle D. outer
4.The numbers given to Jupiter’s moons tell ______.
A. the order in which they were discovered B. the order in which they travel
C. the order of their distance from Jupiter D. the order of names
5.According to the passage，which of the following statements is true？
A. None of Jupiter’s moons have names. B. Most of Jupiter's moons circle clockwise.
C. Jupiter's inner moons were discovered first. D. Jupiter is the nearest planet to the earth.
6.How far away are the middle group of moons from Jupiter？
A. It’s not mentioned. B. 11,100,000 kilometers away.
C. 127,600 kilometers away. D. 20,700,000 kilometers away.
Passage 11
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.
Passage 12
Most animals only have animals of a different kind for food. But sometimes two kinds of animals come together in a partnership (伙伴关系) 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 (寄生虫) 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.
1.Some birds like to sit on a sheep because ________.
A. they can eat its parasites B. they enjoy traveling with the sheep
C. they can’t live without its parasites D. they want to find the warm place
2.The underlined word “they” in the first paragraph means _________.
A. birds and parasites B. birds and sheep
C. parasites and sheep D. birds, parasites and sheep
3.We learn from the passage that corals need plants for _______.
A. friends B. light C. food D. oxygen
4.The Chinese for the word “oxygen” is _________.
A. 氧气 B. 空气 C. 废气 D.二氧化碳
5.What is the second paragraph mainly about?
A. Some animals and plants cannot live without each other.
B. Some animals and plants cannot develop their friendship easily.
C. Some plants eat each other.
D. Some animals live better together.
实战演练答案详解 缤纷自然篇
Passage 1
【答案与解析】这篇短文讲述了某些生物的迁移这一自然现象，并分析了迁移的原因。科学家们最近又研究了龙虾海底成群结队迁移的现象。它们选择在每年天气不好的季节里进行迁移，其中的原因及迁移的目的，科学家尚未弄清楚。
1.C.起初一看，四个选项好像都在文中叙述过，但仔细分析题干中的“most animals”这一关键词语，便可排除其它选项。在第一段最后一句中可找到答案的出处。
2.A。有关“salmon”的情况在第二自然段中作了叙述。这种鱼出生在淡水中，后不到咸水地区居住，在那里度过一生中绝大部分时光。到老了以后又回到它出生之时的淡水之中。仔细分析题干中的“spend a long life”和短文中的关键句“There it spends its life.”便可断定答案为A。
3.B。“they leave their mountain homes when they become too crowded.”一句是答案的出处。
4.B。该题答案的出处是文章的第三自然段。文中说，龙虾是在海底成群结队游动的时间是每年天气不好的季节，目的及它们到哪里去谁也不知道，余项与文章叙述不符。
5.D。文中第二自然段叙述了“salmon”和北欧的一种老鼠迁移方向和原因；第三自然段叙述了龙虾的游动情况，但原因不知道。最后一段开头一句正是对本文主题的概括。
Passage 2
【答案与解析】本文向我们介绍了有关彗星方面的知识。与地球一样，彗星也是绕太阳旋转的，它本身不发光，靠反射太阳的光而发亮。短文中还介绍了彗星的成因，它拖着的长尾巴是如何形成的以及著名的哈雷彗星名字的由来。
1.D。“Like the earth, a comet goes round the sun, but…”是判断本题的根据。
2.C。根据“…is water frozen into pieces of ice and mixed with iron and rock dust and perhaps a few big pieces of rock.”这句话即能得出答案。
3.D。由第五段的首句“Many people perhaps have seen a comet.”可知。
4.C。“Some comets move out of our sight and never come back. Others keep coming back at regular times.”一句是答案的出处。
5.C。哈雷彗星每七十六年才能看到一次。再结合“…the last time it came close to the sun and the earth was in the year 1986.”这句话的意思，即可得到答案。
Passage 3
【答案与解析】这篇短文介绍的是有关植物年轮方面的小知识。由于树木的生长要受到阳光、降水等方面的影响，从一棵树上的年轮分布情况上，可以推断出树木所生长地方以前的气候状况。年轮不仅对科学家研究地球上的气候环境有非常重要的参考价值，而且更为有趣的是，它还能帮助科学家们研究人类的历史呢。
1.A。“If the tenth ring is far from the eleventh ring, then we’re sure that it was sunny and rainy most of that year.”一句即是答案所在。
2.C。文章第一段“Do you know they can tell us what the weather was like…”和第三段的首句“Tree rings are important not only for studying the history of weather…”都有所暗示。
3.A。答案就在 “…to find out the weather of ten years ago, count the rings of a tree from the outside to the inside. If the tenth ring is far from the eleventh ring…”一句中。
4.D。短文最后一段说，人们建房做饭都离不开树木。人所居住的周围环境中如果没有了树木，那么人也就迁移了。所以答案为D。
5.B。根据最后两段所叙述的内容，再联系植物对人类的重要作用，则不难得出答案。
Passage 4
【答案与解析】土壤是人类赖以生存的自然条件之一。没有了土壤或者是土壤受到了较为严重的破坏，就会直接危及到人类的生存。本文在阐述土壤的成因、特性和重要性之后，呼吁大家都要保护土壤。
1.D。综合考虑第一段的意思，唯有D才是最恰当的选项。
2.C。根据“This dark soil is humus, dead leaves, dead plants and animal waste make it, but this takes a long time.”一句所述，可推知这是一种由落叶、枯萎的植物以及动物的粪便在长时间的腐烂后所产生的一种东西。由此不难得出答案为C。
3.D。答案就在“People should grow more and more trees and grass to stop wind from carrying the humus away.”这一句话之中。
4.D。由“When the humus has been made, plants can grow well in it.”和“It takes hundreds of years to make humus,”这两句话所表达的意思，可知答案只能是D。
5.A。本文就是说明土壤对人类的重要性的。事实上，文章结尾的那句话已经点明主旨。
Passage 5
【答案与解析】在大海的温水区域，我们常常可以发现一些珊瑚岛。本文向我们描述了珊瑚岛形成的自然过程。文章最后，作者有感而发，以问句结束全文，发人深思，耐人寻味。
1.B。文章第一段就是讲的“在海中较暖和的水域，常有一些珊瑚岛”这一事实。A显然是不对的。
2.C。根据“A coral island is very nice to look at. It looks like a ring of land with trees, grass, and flowers on it.”这句话不难得出答案。
3.D。答案即在“In each of these holes a very small sea animal has lived. These sea animals make the coral.”一句中。
4.A。倒数第三段中的“Sometimes birds flew over it and brought seeds to the island.”这句话对此有明确的说明。
5.C。由这一小小的自然现象，作者联想到工作在平凡岗位上的工人们，寓意非常深刻。作者的思想感情由最后一段作者的议论可以体会到。
Passage 6
【答案与解析】地震是地球上对人类生存构成威胁的最严重的自然灾害之一。科学家们经过研究，发现了地震活动最频繁的地方。生活在地震带地方的人们可以采取适当的措施减少其危害。也许，将来科学家们能在地震之前预测出发生的地点和时间。
1.D。第一节最后的一句话是本题答案的出处。答案题时，尤其要注意该句中的often一词。
2.B。短文的“When some plates of the earth move suddenly, an earthquake happens”这一句明确告诉我们：地球板块突然移动时，就导致地震的发生。选项A 不是地震的成因，而是地震产生的结果。这从“…the shakings make rocks rise suddenly and even crack open”一句中可以看出。
3.C。地震带(earthquake belts)是可能发生地震的地方。这由第三段的中间几句所描述的内容可知。
4.A。将来科学家能预测出地震发生的时间和地点。有了这种精确的预报，人们当然不会再对地震那么恐惧了。
5.A。短文主要围绕地震的成因、危害以及对未来科学家们从事地震研究的展望，向我们介绍了地震方面的知识。故选项A为最佳答案。
Passage 7
【答案与解析】这是一篇介绍地球的自转、公转以及昼夜的交替等自然现象的成因的短文。借助地理学知识，是不难理解的。
1.B。根据句子的意思及地理课上学到的知识，可知地球绕其中心旋转的那条线叫做地轴。这是一条假想的、看不见的东西。故答案是B。
2.D。根据“The earth travels twenty-four hours around its axis once.”这个句子可直接选出正确答案。事实上，确切地说，地球自转一周所用的时间是23时48分46秒。
3.A。答案就在“… but the sun doesn’t really do so. The turning of the earth makes us feel as if the sun were moving across the sky.”这两句话中。选项D迷惑性较大，但是这利用由地理知识来排除。
4.B。这是表层理解题，很明显答案在“…because everything else on the earth is turning with us”一句中。
5.C。只要理解了“When our half of the earth is facing the sun, we say it is ‘day’. When our half is away from the sun, we say it is ‘night’.”这句话中face的意思，即它在此处用作动词(意思是“对着；面向”)，答案即可迎刃而解。
Passage 8
【答案与解析】这篇短文告诉我们：雌蚊子吸过人的血之后，就会找一个地方去休息一下，然后在叶子或墙上产下许多的卵。蚊子吮吸人的血液令人讨厌，但它对人血还很挑剔呢。有的人，让它叮咬，它还不干呢。如果下一次蚊子叮了你，那说明你与众不同，倍受蚊子青睐。
1.D。“吸血”和“会飞”是mosquitoes的两个主要特征。根据这两个特点，联系生活常识，即可选定答案。另外，读罢全文之后，也能将其余选项予以排除。
2.B。“We know the mosquito very well. Mosquitoes fly everywhere.”一句是答案的出处。
3.D。答案就在“But if she doesn’t like your blood, she will turn to someone else for more delicious blood.”这句话之中。
4.C。答案的依据是“…she lands on your body without letting you know. She bites you so quickly and quietly that you may not feel anything different.”一句。
5. B。其余三项在文中都有明确的说明。根据上面那个小题的内容，B项明显是错误的。
Passage 9
【答案与解析】这篇短文向我们介绍了蜗牛的生活习性。无论是烈日当空，还是大雨滂沱，蜗牛都会像整个冬季一样，呆在壳里睡觉。春天来临的时候，蜗牛就拖着三英寸长的身体从壳里钻出来，靠它那灵敏的触角觅食。别看它的嘴比大头针尖大不了多少，却长着25万多颗牙齿呢！
1.D。根据开头的“But much of the time snails don’t move at all. They are in their shells ----sleeping.”这句话，显然只有D是正确答案。
2.C。本题属熟词新义。由“Hot sun will dry out a snail’s body. So at the least sign of hot sun, a snail draws its body into his shell.”一句的意思，尤其是要仔细考虑关键词“into”对猜测词义的辅助作用，可知蜗牛一旦碰到炙热的太阳，就会把身体蜷缩进壳里。
3.B。答案即是“Its eyes, at the end of the top feelers are very weak.”这句话。
4.D。关键要理解好“So when it rains, a snail does the same thing, too.”这句话中的“the same thing”的意思。事实上，由“In the spring the snail wakes up. … comes out from the shell.”和“…in a hard paper box, it will eat its way out!”是很容易排除B、C和A的。
5.C。根据短文最后一句话“And if a snail wears out its teeth, it will grow new ones.”，可以判断C项是明显的错误。
Passage 10
【答案与解析】这是一篇关于宇宙知识的科普短文。在太阳系中，木星是最大的一颗行星。围绕其旋转的卫星有很多。科学家们首先发现的是离它较近的五颗名叫“内部月亮”的卫星，它们是以逆时针方向绕其旋转的。木星的不计其数的中间月亮团也是以逆时针方向绕其旋转的。但它的最近的四个“外部月亮”却是以顺时针方向绕其旋转的。
1. 选D。文中介绍Jupiter(木星)是最大的行星，地球只有一个月亮，而木星至少有16个，甚至更多。由此可见，solar system即为太阳系，木星同地球一样都是太阳系中的行星。
2. 选A。“clockwise direction”指“顺时针方向”。文中对“counter-clockwise direction”的解释是“opposite of the hands of a clock”，即“逆时针方向”。
3. 选D。最远的四个月亮称为“outer moons”，它们以顺时针方向转。
4. 选A。由文中“The numerals(numbers)tell the sequence, or order, in which the moons were found.”这句话可知。
5. 选C。统观全文，可知选项A、B不符合文意，根据常识判断，选项D也不正确。再由环绕木星旋转的月亮团以依次发现的时间为序，由此推理可得出“the inner moons were discovered first”。
6. 选B。在文中可找到“Jupiter's middle group of moons are at least 11,100,000 kilometers from the planet.”。根据这一句话的意思，便可得知此题答案为B。
Passage 11
【答案与解析】本题以实例说明了太阳对地球上各种生物的重大作用。文中介绍说：太阳是一个巨大的火球，它发出的光和热对于地球上的生物有着非常重要的意义。万物生长靠太阳。动物与人类的食物都来自起始于太阳的食物链。
1.D。答案就在短文首句的“ The sun is a huge, hot, bright star.”之中，其中包含的三个形容词正是本题的答案。
2.A.短文首段末句和第二段的首句“The sun gives us light and heat. All living things need light and heat from the sun to live.”是解答该题目的重要依据。
3.C.本小题属于表层理解题。答案显然在“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.”一句中。
4.B.本小题同样属于表层理解题。“All the food we eat comes from plants in a food chain(链)which starts with the sun.”这句话是问题的出处。此句是定语从句，要仔细阅读才能正确理解。
5.C.根据“It is important because without it there would be no life on Earth.”和“If there was no sun, it would be dark all the time.”这两句话，可很容易将其余三个选项排除。
Passage 12
【答案与解析】自然界中里的事情总是那么的奇妙。很多动物都以不同种类的动物作为自己的食物，有时两种动物还具有伙伴关系呢。有些动物也以植物作为伙伴。比如：海洋生物珊瑚的体内有一种很小的植物。这些植物消耗珊瑚身体内无用的东西，并释放出氧气。而这些氧气又是珊瑚生存所必需的。
1.A.本题属于表层理解题。答案即在“This is not because they want a ride, but because they find easy food in the parasites (寄生虫) on sheep.”一句之中。
2.B.前文中的“The sheep let the birds do so because they can stop the parasites from troubling them.”的意思是说“绵羊让鸟儿落在自己身上，因为鸟儿可以将它们身上的寄生虫吃掉。”；另一句“So though they can do with it by themselves…”的意思是说“尽管它们自己也能对付寄生虫……”。综合上面两句话的意思，再结合“…they can do better together with each other.”这一句话，即得答案。
3.D.显然，根据“…taking the useless things from the coral and giving oxygen in return. That is what the animal needs to live.”这两句话可知，珊瑚需要植物提供的氧气才能生存下去。
4.D.联系生物学常识，氧气是各种生物赖以生存所必需的，所以由此可以推测出该词的意思是“氧气”。
5.A.根据这一自然段的内容，珊瑚和它们体内的植物具有相互依存的关系。因此，答案非A莫属。选项D迷惑性较大。因为这一自然段主要说明了珊瑚与体内植物的关系，它们在一块生存得很好。但选项D意思是“一些动物在一起生存得更好。”只要注意“动物”和“植物”这两个字眼，即可将此项排除。