23.Scientists know a lot about the environment that we should Reduce.Reuse and Recycle . A.which B.who C.whom D.what 查看更多

 

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When the weather is hot, you go to a lake or an ocean. When you are nears lake or an ocean, you feel cool. Why? The sun makes the ear& hot, but it cannot make the water very hot. Although the air over the earth becomes hot, the air over the water keeps cool. The hot air over the earth goes up. Then the cool air over the water moves in and takes the place of the hot air. When you are near a lake or an ocean, you feel the cool air. When it moves in, you feel the wind. And the wind makes you cool. Of course, scientists cannot answer all of our questions, ff you ask, "Why is the ocean full of salt?", scientists will say that the salt comes from rocks. When a rock gets very hot or very cold, it cracks (裂开). Rain falls into the cracks .The rain then carries the salt into the earth and into the rivers. The rivers carry the salt into the ocean. But then we ask, "What happens to the salt in the ocean?" The ocean does not get more salty every year. Scientists are not sure about the answer to the question. We know a lot about our world. But there are still many answers that we don't have, and we are curious(好奇的).

1. Now scientists know_______

A. what makes people feel cool near a lake or an ocean in summer

B. everything about the ocean

C. why the ocean doesn't get more salty

D. what happens to the salt in the ocean

2. In this passage the word "cracks" means _______in Chinese.

A. 山谷       B.裂缝       C. 地壳     D. 岩浆

3. Which of the following is not true?

  A. The sun makes the earth hot.

  B. The sun cannot make the water very hot.

  C. The wind makes you tout.

  D. The hot air over the water moves in and takes the place of the cold air

4. People are always curious about the world because______

A. they know nothing about it      

B. they know little about it

C. there are many answers they do not have     

D. both. A and B

5. The main idea of this passage is that ______

A. the salt in the ocean comes from rocks

B. scientists can explain (解释) everything we want to know

C. people feel cool when they are near a lake or an ocean

D. scientists can explain many things, but not everything

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German scientists say that eating a little chocolate every day may keep you away from cardiovascular(心血管的) disease. The scientists have found that chocolate, especially dark chocolate , can help you cut down 39 percent of heart disease, including taking a very small amount . However, the study advises people not to eat too much chocolate, because too much chocolate is bad for our bodies. So the scientists advise people to eat small amount of chocolate instead of sugar or high-fat snacks.
Scientists said, “Dark chocolate shows the greatest effects, milk chocolate fewer , and white chocolate no effects.” The results showed chocolate may cut down blood pressure, but they also say that further study is needed.
In the eight-year study, people’s daily diet, exercise habits, and blood pressure were studied in 19,357 persons aged 35 to 65. They found that people who are an average of 7.5 grams of chocolate a day had a very lower chance of heart disease than those who ate much less chocolate , and average of 1.7 grams a day.
【小题1】It took the scientists __________ years to prove that small amount of chocolate is good for people.

A.8B.35C.39D.65
【小题2】In the study, scientists studied _______________.
A.where chocolate came from
B.how chocolate was made
C.people’s daily diet, exercise habit and blood pressure
D.why people liked chocolate so much
【小题3】From the passage, we know that _________________.
A.chocolate was popular in Germany before
B.chocolate is good for us, but we should not eat too much
C.eating 1.7 grams of chocolate each time is the best
D.people aged 35 had better not eat chocolate

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Some people like to get up late, but some do not. In fact, it is really good for us to get up early every day. Maybe those who don't like getting up early will not believe this, but it is true.

Scientists made a survey in about one thousand people, and then they found that early rising people had less disease than late rising people, and early rising people also looked healthier than late rising people, and so on.

So we may know early rising is helpful in more than one way. First, it helps to keep us healthy. We all need fresh air. But air is never as fresh as early in the morning. Besides, it is useful to do morning exercises.

Secondly, early rising helps us in our studies. In the morning we learn more quickly and find it easier to understand what we learn.

Thirdly, early rising can give us a plan of our work for the day. We cannot work well without a good plan.

Fourthly, early rising gives us enough time to get ready for our work^ such as to wash our hands and faces and eat our breakfast.

Late risers may find it difficult to form the habit of early rising. They have to make an effort (努力)to do so. As the English proverb says, “Early to bed and early to rise makes a man healthy, wealthy and wise•”

Judge the following sentences true (T) or false (F) according to the passage.

1.People don't always agree on whether to e»et up early.

2. In the passage the writer gives four reasons for early rising.

3. Early rising makes people happier according to the passage.

4.Early risers don't look as healthy as late risers.

5.The writer encourages people not to sleep late.

 

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Can dolphins talk? Maybe they can’t talk with words, but they talk with sounds. They show their feelings with sounds.
Dolphins travel in a group. We call a group of fish a “school”. They don’t study, but they travel together.
Dolphins are mammals(哺乳动物), not fish, but they swim together in a school. Dolphins talk to the other dolphins in the school. They give information. They tell when they are happy or sad or afraid. They say“welcome”when a dolphin comes back to the school. They talk when they play.
They make a few sounds above water. They make many more sounds under water. People can’t hear these sounds because they are very, very high. Scientists make tapes of the sounds and study them.
Sometimes people catch a dolphin for a large aquarium.(An aquarium is a zoo for fish.) People can watch the dolphins in a show. Dolphins don’t like to be away from their school in an aquarium. They are sad and lonely.
There are many stories about dolphins. They help people. Sometimes they save somebody’s life. Dolphin meat is good, but people don’t like to kill them. They say that dolphins bring good luck. Many people believe this.
【小题1】A school of dolphins means_____.

A.a zoo for dolphinsB.a show by dolphins
C.a group of dolphinsD.a library of dolphins
【小题2】 A dolphin feels _____in an aquarium.
A.afraid
B.happy with people watching them
C.lucky
D.sad and lonely
【小题3】Which sentence is true?
A.Dolphins talk with words.
B.Dolphins always bring good luck.
C.Dolphins make more sounds above water.
D.Dolphins can’t breathe(呼吸) under the water.
【小题4】People can’t hear the dolphins’ sounds because they are         .
A.lowB.highC.softD.quiet
【小题5】From the passage we know_____.
A.Dolphins travel together.
B.Dolphins talk with words when they play.
C.Dolphins like to live in aquariums.
D.All people want to catch dolphins and eat them.

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Oriole’s Nest
Picky, Picky
Scientists have no idea exactly why birds choose certain objects to build their nests. But scientists know that the main reason birds build nests is to keep their babies safe, warm and healthy.
Baby birds grow faster and are healthier when they are warm. They also learn to fly and leave the nests sooner than birds without warm homes.
What A Yarn (纱)
Yarn is big on an oriole’s shopping list during nest building. Scientists are still trying to work out why so many birds choose white yarn over other colors for nest building.
Scientists think that the white objects remind birds of cotton fluff (绒毛) they find in the wild.
Do It Naturally  
Even though birds can help us recycle some of our junk by using it to build nests, they also need to use lots of natural things. Long grass, dried sticks, spider’s silk and mud are some of the natural ingredients that are good for nests, too.
You can make a collection box of things to leave for birds so they can help themselves. Hang a small plastic box with holes on a tree branch. Fill the box freely with nest building goodies. Hang the box on a tree and watch birds climb on board to pick through the junk to find their treasures.
Warning: Don’t let the birds turn into a tasty treat. Keep your bird station away from places where cats hang out.
For The Birds!
Stop! Don’t throw all that garbage out! Give some to the birds. Look and see how your old junk can help beautify and warm a bird’s new home.
【小题1】The baby birds with warm homes are able to _____.
A.choose right objectsB.leave the nests sooner
C.build good nestsD.learn to fly higher
【小题2】 What can people make for birds to build nests?
A.Holes on the tree.B.Food out of the rubbish.
C.A warning board.D.A collection box of things.
【小题3】What can we learn from the passage?
A.Birds build nests to store things.
B.Birds regard white objects as cotton.
C. Birds and humans can help each other.
D.Birds and cats fight against each other.

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