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 answ
er 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 |
Did you know that a turtle（乌龟）can lay 12 eggs in one minute? A large sea turtle lays around 150 eggs at a time. She lays all these eggs in just a few minutes..
Large sea turtles live in the warm seas of the world. Except for when they lay their eggs, they spend their whole lives in the water. When it is time to lay their eggs, the females swim to land..
They usually return to the place where they themselves were born. How they find their way back there is unknown. When they reach shore, the big, heavy turtles crawl slowly up to the high water mark. Using their flippers（脚蹼）, they pull themselves along the sand. They must struggle like mountain climbers. When they finally reach dry sand, they rest before beginning the difficult task of laying eggs.
The turtles lay the eggs in deep holes and cover them with warm sand. The sand protects the eggs from harm. Then the females leave them. After a few weeks, if you happened to be walking along the beach, you might see the sand begin to shake. You may see tiny black balls coming out of the sand. The tiny heads of baby turtles!The first sentence lets us know that this passage is about _____.
A. speed B. turtles C. time D oceans.Turtles bury their eggs to protect them from _____.
| A．deep water | B．heat |
| C．danger | D．bad weather |
We can conclude from this passage that _____.
| A．many turtles die while swimming to shore |
| B．female turtles protect their babies |
| C．once turtles land, they never return to the sea |
| D．the job of laying eggs takes great strength |
The writer compares turtles to climbers _____.
| A．because they lay their eggs in mountain areas |
| B．to give you a picture of how hard they work |
| C．to tell you that they like to climb |
| D．to show that mountain climbers are as slow as turtles |
B
| Populations and Land (1987) |
||||
| Area in |
Percent |
Population |
Percent |
|
| Square miles |
Cultivated |
In millions |
forested |
|
| United States |
3615104 |
20 |
243.8 |
28 |
| Canada |
3851792 |
5 |
25.9 |
33 |
| United Kingdom |
94525 |
29 |
56.8 |
9 |
| Australia |
2967896 |
6 |
16.2 |
14 |
| India |
1269340 |
51 |
800.3 |
21 |
| China |
3705390 |
11 |
1062.0 |
14 |
Which two countries are the closest to each other in area?
| A．The US and Canada | B．The US and China |
| C．China and Canada | D．India and China |
_____ has the highest population density(密度), and _____ has the second highest.
| A．China, India | B．India, China |
| C．India, the US | D．China, the US |
Which two countries have the closest percentage of cultivated land?
| A．The US and the United Kingdom. |
| B．The US and China |
| C．Australia and Canada． |
| D．Australia and China |
There are _____ countries whose cultivated land percentage is larger than the forest percentage.
| A．2 | B．3 | C．4 | D．5 |
Good afternoon，and welcome to England. We hope that your visit here will be a pleasant one. Today，I would like to draw your attention to a few of our laws.
The first one is about drinking. Now，you may not buy alcohol in this country. If you are under 18 years of age，nor may your friends buy it for you.
Secondly，noise. Enjoy yourselves by all means，but please don’t make unnecessary noise，particularly at night. We ask you to respect other people who may wish to be quiet.
Thirdly，crossing the road. Be careful！The traffic moves on the left side of the road in this country. Use pedestrian crossings and do not take any chances when crossing the road.
My next point is about litter (throwing away waste material in a public place)．It is an offence (违法行为) to drop litter in the street. When you have something to throw away，please put it in your pocket and take it home，or put it in a litter bin.
Finally，as regards something，it is against the law to buy cigarettes or tobacco if you are under 16 years of age.
I’d like to finish by saying that if you require any sort of help or assistance，you should contact your local police，who will be pleased to help you.
Now，are there any questions?The main purpose of this speech would be to________.
| A．prepare people for international travel |
| B．declare the laws of different kinds |
| C．give advice to travelers to the country |
| D．inform people of the punishment for breaking laws |
The underlined word “contact” in the 7th paragraph means________.
| A．keep in touch with | B．join |
| C．report | D．get in touch with |
From the speech we learn that________.
| A．In this country，if you are under 18 years of age，you may not buy alcohol，but your friend can buy it for you |
| B．you may not buy cigarettes or tobacco unless you are above 16 years of age |
| C．because the traffic moves on the left side of the road，you must use pedestrian crossings when crossing the road |
| D．you can’t make noise except at night |
Have you ever complained why life is so tiring? Does the sky sometimes seem dark to you? Are your studies sometimes not successful? Well, friends, cheer up and smile all the time. If you see the world with your warm heart, you’ll find that the whole world smiles to you.
While in school, sometimes you are tired of your lessons, but have you ever noticed the happy smile on your teacher’s face when you did a good job?
One day it is fine. Just before you go out, it suddenly starts to rain. Maybe you would feel very sad and start to complain about the weather. But dear friends, why don’t you sit down and listen to the free concerts that the nature offers you? And with the timely rain, crops in the fields will grow better and better and farmers will have a good harvest.
Although everyone wants to succeed in what he tries to do, sometimes failure can’t be avoided. I think failure is not terrible, and the terrible thing is that we are afraid of it and give up hope. When we face failure, we must be confident in ourselves, draw a useful lesson from it and try our best to finish what we have decided to do. As a popular saying goes, “Failure is the mother of success”.
Attitude decides everything. With an optimistic attitude life is easy and pleasant. Let’s smile to whatever we meet and the whole world will smile to us.People sometimes complain _________.
| A．the sky is always dark |
| B．their studies are successful |
| C．they see the world with their heart |
| D．life is tiring |
When we face failure, we ___________.
| A．must be confident in ourselves |
| B．shouldn’t be afraid of it |
| C．shouldn’t give up hope |
| D．All of the above |
The best title for the passage is_______.
| A．Smile and the World Smiles to You |
| B．Complaining about Life |
| C．Failure is the Mother of Success |
| D．It is Very Hard to Succeed |
More than two thirds of the world's polar bears will be wiped out by 2050，according to a shocking new study. By then，scientists say，global warming will have melted 42 percent of the Arctic sea ice. By 2100，only a very few of these important creatures will be left.
The report has been produced by the US Geological Survey. The scientists have publicized their findings in the hope of influencing US Interior Secretary Dirk Kempthorne，who has been asked to put polar bears on the US endangered species list.
Polar bears depend on floating sea ice as a platform for hunting seals，which are their main food. Without enough ice，polar bears would be forced to go onto the land，where they are poorly skilled hunters，and would be unlikely to adapt to the life on the land in time. Experts say few little bears would survive and the stress could make many females unable to get pregnant.
The team of American and Canadian scientists spent six months studying bears，on the ground，from spotter planes and in the lab，using computer models.
Some team members fear the result is even worse for the bears than what their report says. They say the Arctic is warming faster than anywhere in the world and much faster than their computer had been forecasting. Satellite observations have showed that the ice has decreased to an all－time low.
However，not everyone in the scientific community believes that global warming is happening on such an alarming scale. Another investigation has found that polar bears are still being hunted by wealthy “sportsmen” who want their skins and heads. At least ten international companies offer bear－hunting trips.What do we know about Dirk Kempthorne according to the passage?
| A．He is an animal scientist. |
| B．He is a protector of animals working for the US government. |
| C．He was asked to put polar bears on the US endangered species list. |
| D．He offered to put polar bears on the endangered species list. |
Why will polar bears die out if there is not enough sea ice?
| A．Because polar bears can't catch enough food without ice. |
| B．Because polar bears eat ice when they feel thirsty. |
| C．Because polar bears will be easily found by hunters without ice. |
| D．Because most female bears are used to giving birth under ice. |
After a six－month study，some scientists fear that ________．
| A．there is something wrong with their computers |
| B．polar bears will disappear even faster than they ever expected |
| C．their computer models are not as accurate as they expected |
| D．global warming will destroy everything in the Arctic |
What does the writer want to tell us in the last paragraph?
| A．The forecast about the future of polar bears is not correct. |
| B．Global warming won't have any effect on hunting trips in the Arctic. |
| C．Polar bears are an endangered species as a result of bear－hunting. |
| D．People don't pay enough attention to the protection of endangered species. |