It is natural that children are curious (好奇的) about the world around them. For example, they want to know how their hearts beat. They want to know why the ocean water tastes salty.

　　As children grow up, they become curious about different kinds of things. When they are babies, they are interested in the parts of their bodies and in the smiles of their mothers. They become interested in the physical world around them: the plants, the animals, the sky. Later, they become interested in the things that people have made: wheels, bicycles, cars. And when they are adults, their curiosity continues. Sometimes this curiosity leads to a career (生涯、职业) in science.

　　Scientists spend their lives trying to find out about the world．Those who work with the earth sciences study the earth, the oceans, and the skies. Other scientists who study living things work with the biological sciences. A third group of scientists study the physical sciences, e. g. physics, chemistry .

　　These scientists have already discovered a lot about our world．For example, they tell us why your heart beats fast when you run. They say that when you are quiet, your heart normally beats sixty-five or seventy-five times a minute. Your heart is a pump (泵) that pumps blood to all parts of the body. The blood carries oxygen and nutrition. When you run, your muscles work very hard and use the nutrition that the blood carries to them. The muscles need oxygen, too . So your brain sends a signal to the heart. The signal means that the muscles need more nutrition and oxygen. Then the heart beats fast and sends blood quickly to the muscles. It may beat 90 to 140 times a minute.

　　Of course, scientists cannot answer all of our questions. If we ask, “Why does the ocean water taste salty” scientists will say that the salt comes from rocks. When a rock gets very hot or very cold, it cracks. Rain falls into 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 saltier every year.” Scientists are not sure about the answer to this question.

　　We know a lot about our world, but there are still many answers that we do not have, and we are curious.

1.According to the passage, which of the following statements is true?

　 A. People are curious in the same way.

　 B. People in different countries are interested in different things.

　 C. Men and women are curious about different things.

　 D. People of different ages are interested in different things

2.Scientists who work with the biological sciences study____.

A. the earth , the oceans and the sky                 B. man-made things

C. plants and animals               D. ocean water

3.A rock cracks _____.

A. in wet regions                                     B. in dry regions

C. at very high or very low temperatures     D. when salty water falls in

4. People are always curious because ____.

A. they cannot explain many things B. they know nothing about the world

C. they know little about the world  D. they want to be scientists

 

He knows little of mathematics，______ of chemistry.

　　A. as well as  B. no less than    C. still less   D. no more than

Fish Ears Tell Fish Tales

　 Fish have ears. Really. They’re quite small and have no opening to the outside world carrying sound through the body. For the past seven years, Simon Thorrold, a university professor, has been examining fish ears, small round ear bones called otoliths (耳石).

　 As fish grow, so do their otoliths. Each day, their otoliths gain a ring of calcium carbonate (碳酸钙). By looking through a microscope and counting these rings, Thorrold can determine the exact age of a young fish. As a fish gets older, its otoliths no longer get daily rings. Instead, they get yearly rings, which can also be counted, giving information about the fish’s age, just like the growth rings of a tree.

　 Ring counting is nothing new to fish scientists. But Thorrold has turned to a new direction. They’re examining the chemical elements (元素) of each otolith ring.

　 The daily ring gives us the time, but chemistry tells us about the environment in which the fish swam on any given day. These elements tell us about the chemistry of the water that the fish was in. It also says something about water temperature, which determines how much of these elements will gather within each otolith ring.

　 Thorrold can tell, for example, if a fish spent time in the open ocean before entering the less salty water of coastal areas. He can basically tell where fish are spending their time at any given stage of history.

　 In the case of the Atlantic croaker, a popular saltwater food fish, Thorrold and his assistant have successfully followed the travelling of young fish from mid-ocean to the coast, a journey of many hundreds of miles.

　 This is important to managers in the fish industry, who know nearly nothing about the whereabouts of the young fish for most food fish in the ocean. Eager to learn about his technology, fish scientists are now lending Thorrold their ears.

1.What can we learn about fish ears from the text?

　A. They are small soft rings.

　B. They are not seen from the outside.

　C. They are openings only on food fish.

　D. They are not used to receive sound.

2.Why does the writer compare the fish to trees?

　A. Trees gain a growth ring each day.

　B. Trees also have otoliths.

　C. Their growth rings are very small.

　D. They both have growth rings.

3.Why is it important to study the chemistry of otolith rings?

　A. The elements of the otoliths can tell the history of the sea.

　B. Chemical contents of otoliths can tell how fast fish can swim.

　C. We can know more about fish and their living environment.

　D. Scientists can know exactly how old a fish is.

4.How would you understand “fish scientists are now lending their ears”?

　A. They are very interested in Thorrold’s research findings.

　B. They want to know where they can find fish.

　C. They lend their fish for chemical studies.

　D. They wonder if Thorrold can find growth rings from their ears.　

 

It is natural that children are curious (好奇的) about the world around them. For example, they want to know how their hearts beat. They want to know why the ocean water tastes salty.

　　As children grow up, they become curious about different kinds of things. When they are babies, they are interested in the parts of their bodies and in the smiles of their mothers. They become interested in the physical world around them: the plants, the animals, the sky. Later, they become interested in the things that people have made: wheels, bicycles, cars. And when they are adults, their curiosity continues. Sometimes this curiosity leads to a career (生涯、职业) in science.

　　Scientists spend their lives trying to find out about the world. Those who work with the earth sciences study the earth, the oceans, and the skies. Other scientists who study living things work with the biological sciences. A third group of scientists study the physical sciences, e. g. physics, chemistry .

　　These scientists have already discovered a lot about our world. For example, they tell us why your heart beats fast when you run. They say that when you are quiet, your heart normally beats sixty-five or seventy-five times a minute. Your heart is a pump (泵) that pumps blood to all parts of the body. The blood carries oxygen and nutrition. When you run, your muscles work very hard and use the nutrition that the blood carries to them. The muscles need oxygen, too . So your brain sends a signal to the heart. The signal means that the muscles need more nutrition and oxygen. Then the heart beats fast and sends blood quickly to the muscles. It may beat 90 to 140 times a minute.

　　Of course, scientists cannot answer all of our questions. If we ask, “Why does the ocean water taste salty” scientists will say that the salt comes from rocks. When a rock gets very hot or very cold, it cracks. Rain falls into 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 saltier every year.” Scientists are not sure about the answer to this question.

　　We know a lot about our world, but there are still many answers that we do not have, and we are curious.

According to the passage, which of the following statements is true?

　 A．People are curious in the same way.

　 B．People in different countries are interested in different things.

　 C．Men and women are curious about different things.

　 D．People of different ages are interested in different things

Scientists who work with the biological sciences study____.

    A．the earth , the oceans and the sky   B．man-made things

    C．plants and animals   D．ocean water

When you run, your muscles need ____.

A．more nutrition and oxygen    B．more signals   

C．more salt                  D．water

A rock cracks _____.

A．in wet regions       B．in dry regions

C．at very high or very low temperatures     D．when salty water falls in

People are always curious because ____.

A．they cannot explain many things  B．they know nothing about the world

C．they know little about the world  D．they want to be scientists

B

It is natural that children are curious about the world around them. For example, they want to know how their hearts beat. They want to know why the ocean water tastes salty.

　　As children grow up, they become curious about different kinds of things. When they are babies, they are interested in the parts of their bodies and in the smiles of their mothers. They become interested in the physical world around them: the plants, the animals, the sky. Later, they become interested in the things that people have made: wheels, bicycles, cars. And when they are adults, their curiosity continues. Sometimes this curiosity leads to a career (生涯、职业) in science.

　　Scientists spend their lives trying to find out about the world．Those who work with the earth sciences study the earth, the oceans, and the skies. Other scientists who study living things work with the biological sciences. A third group of scientists study the physical sciences, e. g. physics, chemistry .

　　These scientists have already discovered a lot about our world．For example, they tell us why your heart beats fast when you run. They say that when you are quiet, your heart normally beats sixty-five or seventy-five times a minute. Your heart is a pump (泵) that pumps blood to all parts of the body. The blood carries oxygen and nutrition. When you run, your muscles work very hard and use the nutrition that the blood carries to them. The muscles need oxygen, too . So your brain sends a signal to the heart. The signal means that the muscles need more nutrition and oxygen. Then the heart beats fast and sends blood quickly to the muscles. It may beat 90 to 140 times a minute.

　　Of course, scientists cannot answer all of our questions. If we ask, “Why does the ocean water taste salty” scientists will say that the salt comes from rocks. When a rock gets very hot or very cold, it cracks. Rain falls into 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 saltier every year.” Scientists are not sure about the answer to this question.

　　We know a lot about our world, but there are still many answers that we do not have, and we are curious.

45．According to the passage, which of the following statements is true?

　  A．People are curious in the same way.

　  B．People in different countries are interested in different things.

　  C．Men and women are curious about different things.

　  D．People of different ages are interested in different things

46．Scientists who work with the biological sciences study____.

A．the earth , the oceans and the sky          B．man-made things

C．plants and animals                               D．ocean water

47．When you run, your muscles need ____.

A．more nutrition and oxygen    B．more signals    C．more salt   D．water

48．A rock cracks _____.

A．in wet regions                                     B．in dry regions

C．at very high or very low temperatures               D．when salty water falls in