With more forests being destroyed, huge quantities of good earth each year. A. is washing away B. is being washed away C. are washing away D. are being washed away 查看更多

 

题目列表(包括答案和解析)

Thirty years ago, Lake Ponkapog in Hartwell, New Jersey, was full of life. Many birds and animals lived beside the water, which was full of fish. Now there are few birds, animals, and fish. The lake water is polluted. It is in a colour of dirty brown, and it is filled with strange plants.

How did this happen? First, we must think about how water gets into Lake Ponkapog. When it rains, water comes into the lake from all around. In the past, there were forests all round Lake Ponkapog, so the rainwater was clean.

Now there are many homes around the lake. People often use the chemicals (化学制品)in their gardens. They use other chemicals inside their houses for cleaning and killing insects. There are also many businesses. Businesses use chemicals in their machines of shops. Other chemicals fall onto the ground from cars or trucks. When it rains, the rainwater picks up all the chemicals from home and businesses and then carries them into the lake . They pollute the water and kill the animals.

Boats on the lake are also a problem. Lake Ponkapog is a popular place for motorboats(汽船). But oil and gas from boats often get into the lake. So more bad chemicals go into the water this way.

People in Hartwell are worried . They love their lake and want to save it. Will it be possible? A clean lake must have clean rainwater going into it. Clean rainwater is possible only if people are more careful about chemicals at home and at other chemicals on the ground. And they mustn’t use motorboats any more on the lake. All these may change people’s lives. Only then can Lake Ponkapog be a beautiful, clean lake again.

1.In the past, the water in Lake Ponkapog was made clean by ________.

A.forests           B.rain              C.birds             D.fish

2.Chemicals from homes and businesses _________.

A.are always clean                        B.can help the animals

C.are good for the lake                     D.get into the rainwater

3.Cleaner rainwater will mean _________ .

A.more boats on the lake                   B.more dirty things in the lake

C.a cleaner lake                          D.a dirty lake

4.To save Lake Ponkapog, people need to ________.

A.be more careful about chemicals           B.use the water

C.grow fewer plants in the gardens            D.use more motorboats on the lake

5.The passage is about ________.

A.boats on the Lake Pankapog               B.why the water is dirty in Lake Ponkapog

C.clean rainwater                         D.dirty lakes

 

查看答案和解析>>

When you watch TV programs about wild animals, it is surprising to see how an antelope (羚羊) can run away from a strong lion. In the wilderness, everyone has his own way to protect himself. Even plants have their own ways to fight off enemies.

Over millions of years, plants have developed their own defense system (防卫系统). Chemicals are fantastically used by plants to survive (幸存). By making their leaves, flowers, roots and fruits poisonous (有毒的) to enemies, plants can fight back.

One such plant is the Golden Wattle tree. The British scientist David Cameron has found when an animal eats the tree’s leaves, the amount (数量) of poison increases in the other leaves. “It’s like the injured leaves telephoning the others to fight together against the enemy,” he said.

The tree also sends defense messages to neighboring plants by giving out a special smell. Golden Wattle trees in the nearby 45 meters will get the message and produce more poison within 10 minutes. Now, if an enemy eats too many of the trees’ leaves, he will die.

Every kind of plant or tree is good at producing a special set of chemicals. Herbivores, like rabbits, can safely eat the leaves of one tree, but they may be poisoned by its neighbor.

In this way, plants have not only developed their own defense system, but also shared it with others. This makes it impossible for a single animal to destroy even a small area of forest.

1.From the first 2 paragraphs, we can learn that _________.

A. plants can do nothing against their enemies

B. chemicals are quite useful for plants to survive

C. an antelope can always run away from a strong lion

D. leaves, roots, flowers and fruits of plants are poisonous

2.If animals eat one Golden Wattle tree’s leaves, the tree can________.

A. kill the animals with a special smell

B. tell other trees to come to protect it

C. warn other trees against the animals on the phone

D. send defense messages to the neighboring plants

3.The underlined word “herbivores” in the 5th paragraph probably means animals which _____.

A.produce poison                                     B.live on small animals

C.like to eat rabbits                                       D.feed on plants or grass

4.The last paragraph of the passage suggests that this kind of defense system is ________.

A.bad for animals                                        B.good for forests

C.helpful to some animals                        D.harmful to forests

5.The passage is mainly about __________.

A.the examples of protecting forests

B.the balance between animals and plants

C.the ways of plants fighting against enemies 

D.the relationship between lions and antelopes

 

查看答案和解析>>

When you watch TV programs about wild animals, it is surprising to see how an antelope (羚羊) can run away from a strong lion. In the wilderness, everyone has his own way to protect himself. Even plants have their own ways to fight off enemies.

    Over millions of years, plants have developed their own defense system (防卫系统). Chemicals(化学物) are fantastically used by plants to survive . By making their leaves, flowers, roots and fruits poisonous (有毒的) to enemies, plants can fight back.

    One such plant is the Golden Wattle tree. The British scientist David Cameron has found when an animal eats the tree's leaves, the amount (数量) of poison increases in the other leaves. "It's like the injured leaves telephoning the others to fight together against the enemy", he said.

    The tree also sends defense messages to neighboring plants by giving out a special smell. Golden Wattle trees in the nearby 45 meters will get the message and produce more poison within 10 minutes. Now, if an enemy eats too many of the trees' leaves, he will die.

    Every kind of plant or tree is good at producing a special set of chemicals. Herbivores, like rabbits, can safely eat the leaves of one tree, but they may be poisoned by its neighbor.

    In this way, plants have not only developed their own defense system, but also shared it with others. This makes it impossible for a single animal to destroy even a small area of forest.

1.From the first 2 paragraphs, we can learn that_______.

A. plants can do nothing against their enemies

B. chemicals are quite useful for plants to survive

C. an antelope can always run away from a strong lion

D. leaves, roots, flowers and fruits of plants are poisonous

2.The underlined word "herbivores" in the 5th paragraph probably means animals which_______.

A. produce poison                            B. live on small animals

C. like to eat rabbits                 D. feed on plants or grass

3.The last paragraph of the passage suggests that this kind of defense system is_______.

A. bad for animals                             B. good for forests

C. helpful to some animals    D. harmful to forests

4.The passage is mainly about_____________________.

A. the examples of protecting forests

B.the balance between animals and plants

C. the ways of plants fighting against enemies

D. the relationship between lions and antelopes

 

查看答案和解析>>

Do you know why different animals or insects have their special colors? Colors are used mainly to protect themselves.

Why can’t some birds easily catch locusts(蝗虫)? It is because locusts change their colors together with the change of the colors of crops. When crops are green, locusts look green. But as autumn comes, locusts change to the same brown color as crops have. Some other insects with different colors from plants are easily found and eaten by others. So they have to hide themselves for lives in the day and appear only at night.

If you study the animal life, you’ll find the main use of coloring is to protect themselves. Bears, lions and other animals can’t be easily seen by hunters. This is because they have the colors much like the trees.

Have you ever noticed an even more strange thing? A kind of fish in the sea can send out black liquid when it faces danger. While the liquid spreads over, its enemies can’t find it. And it quickly swims away. So it has lived up to now though it is not strong at all.

1. From the article we learn that locusts          .

A. are dangerous to their enemies           B. are easily found by birds

C. change their colors to protect themselves   D. are small animals

2.How can insects with different colors from plants keep out of danger?

A. They have to move quietly.

B. They hide themselves in the day and appear at night.

C. They have the colors much like their enemies.

D. They run away quickly.

3. Bears and lions can keep safe because          .

A. they live in forests                  B. they like brown and grey colors

C. they move quietly                    D. they have the colors similar to the trees

4.What does the word “liquid” mean in the last paragraph?

A. 气体          B. 固体        C. 液体        D. 水蒸气

5. Which is the best title for this passage?

A. The Main Use of Colors for Animals and Insects

B. Colors of Different Animals and Insects

C. The Change of Colors for Animals and Insects

D. The Change of Different Animals and Plants

 

 

查看答案和解析>>

People often say that the earth is like our mother. She gives life to all the living things on the earth and provides us with air, food, water and other essential things we need for living.
Once she was beautiful and rich, but now she becomes dirtier and dirtier, poorer and poorer. It is due to what we have done to her. Please have a good look at her: polluted rivers and lakes, growing deserts, the destruction of the forests and wild life, and the depletion (消耗,用尽) of the ozone layer (臭氧层)...
Can she bear to see her children putting the waste here and there? Can she bear to see her children cutting down the trees and destroying the grassland, to see the acid rain destroying everything? Can we bear to see our mother suffering (受苦) so much? Isn’t it time for us to ask ourselves whether this is the way to treat our mother?
Floods, droughts, acid rain..., these are the punishments (惩罚) from nature. Everyone should know that there is only one earth. If we go on treating her like this, it won’t be fit for us to live in any longer. It’s time for us to love her, take good care of her and cure her. We should save the earth so as to save ourselves.
【小题1】 What does the earth look like now?
A.It has clean rivers, lakes and green forests.
B.It is like a beautiful girl.
C.It is more beautiful and richer.
D.It is dirtier and dirtier, poorer and poorer.
【小题2】 What is the meaning of the underlined word?
A.KnowB.StandC.ImagineD.Hear
【小题3】 What is the best title of the passage?
A.The earth—our mother.
B.Defenders of the Earth (地球卫士).
C.The earth is very beautiful and healthy.
D.The water on the earth is very clean.

查看答案和解析>>


同步练习册答案