A Brown University sleep researcher has some advice for people who run high schools: Don’t start classes so early in the morning. It may not be that the students who nod off at their desks are lazy. And it may not be that their parents have failed to enforce(确保) bedtime. Instead, it may be that biologically(生物学上)these sleepyhead(贪睡者)students aren’t used to the early hour.
　　“Maybe these kids are being asked to rise at the wrong time for their bodies,” says Mary Carskadon, a professor looking at problem of adolescent (青春期的)sleep at Brown’s School of Medicine.
　　Carskadon is trying to understand more about the effects of early school time in adolescents. And, at a more basic level, she and her team are trying to learn more about how the biological changes of adolescence affect sleep needs and patterns(方式).
　　Carskadon says her work suggests that adolescents may need more sleep than they did at childhood, no less, as commonly thought.
　　Sleep patterns change during adolescence, as any parent of an adolescent can prove. Most adolescents prefer to stay up later at night and sleep later in the morning. But it’s not just a matter of choice---their bodies are going through a change of sleep patterns.
　　All of this makes the transfer(迁移)from middle school to high school---which may start one hour earlier in the morning----all the more difficult, Carskadon says. With their increased need for sleep and their biological clocks set on the “sleep late, rise late” pattern, adolescents are up against difficulties when they try to be up by 5 or 6 a.m. for a 7:30 a.m. first bell. A short sleep on a desktop may be their body’s way of saying. “I need a timeout.”
【小题1】Carskadon suggests that high schools should not start classes so early in the morning because _______.

A．it is really tough for parents to enforce bedtime

B．it is biologically difficult for students to rise early

C．students work so late at night that they can’t get up early

D．students are so lazy that they don’t like to go to school early

【小题2】The underlined phrase nod off most probably means _______.

A．turn around

B．agree with others

C．fall asleep

D．refuse to work

【小题3】What might be a reason for the hard transfer from middle school to high school?

A．Adolescents depend more on their parents.

B．Adolescents have to choose their sleep patterns.

C．Adolescents sleep better than they did at childhood.

D．Adolescents need more sleep than they used to.

【小题4】What is the test mainly about?

A．Adolescent health care.

B．Problems in adolescent learning.

C．Adolescent sleep difficulties.

D．Changes in adolescent sleep needs and patterns.

In China , more and more middle school students are getting shorter sleeping time than before. Most students sleep less than nine hours every night, because they have much homework to do. Some homework is given by their teachers, and some by their parents. Also, some students don't know how to save time. They are not careful enough while they do their homework, so it takes them a lot of time. Some students spend too much time watching TV or playing computer games. They stay up (熬夜) very late. Some students have to get up early every morning on weekdays to get to school on time by bus or by bike. It can be a long way from home to school.

　　Schools and parents should cut down some of the homework so that our children can enjoy more than nine hours of sleep every night for their health. For children, we should make best use of our time. When we have enough time for sleeping, we will find it much better for both our study and health.

1.What makes most students sleep less than nine hours every night?

　　    A. Watching TV.

B. Playing computer games.

　　    C. Doing their homework.

D. Doing housework.

2.Who else gives children some homework to do except their teachers?

　　   A. Their parents.　　　　　　　　　　　B. Other students.

　　   C. The children themselves.　　　　　　 D. Nobody else.

3.How many hours of sleep is good for students' health?

　　  A. Less than 9 hours.　　B. Over 9 hours.　　

C. Only 9 hours.　    　D.8 hours.

4.What would happen to a student who often goes to bed late and gets up early?

　　   A. He would fall asleep in class.

B. He would do well in study.

　　   C. He would finish his homework fast.

D. He would have good health.

5.Which of the following is NOT true?

　　   A. Some students are so careless that they spend lots of time on their homework.

　　   B. All the students stay up late for their homework.

　　   C. Children should be given less homework.

   D. Schools and parents should take care of children.

 

Computers can injure you. Most other injuries happen suddenly. For example, if you fall off a bike and break your arms, it happens very quickly. But computer injuries slowly.

　 You probably know how to ride a bike safely. Now learn to use a computer safely.

Your eyes

　 Too much light can injure your eyes, so never sit too close to a computer screen. Your eyes should be at least 50 centimeters from the screen. Remember to look away from it sometimes. This gives your eyes a rest.

　 When you use a computer, the window should be on your left or your right. If it is behind you, the light will reflect on (反射) the screen. If the window is in front of you, the sun and the screen will both shine into your eyes.

Your hands and wrists (手腕)

　　Hand and wrist injuries can happen because the hands and wrists are moved in the same way hundreds of times. If you use a keyboard for a long time, follow these three rules: 1) Rest your wrists on something. 2) Keep your elbows (肘部） at the same height as the keyboard. 3) Stop something and exercise your hands, wrists and fingers in a different way.

Your back

　　Some people sit for many hours in front of a computer. If you sit in the wrong way, you can injure your back or your neck. So you should sit with your back straight. The top part of the screen should all be in front of your eyes. Your forearms（前臂）, wrists, hands and the upper（上部） part of your legs should all be parallel (平行) to the floor. If you are sitting for a long time, get up every 30 minutes and exercise your arms, legs and necks.

　 Enjoy your computer, but use it safely.

1.A computer screen may injure your eyes if __________.

A．you sit 60 centimeters away

B．you remember to look away

C．your eyes are too close to it

D．the window is on your left or your right

2.Hand and wrist injuries are caused when you _________.

A．get plenty of exercise

B．move in the same way again and again

C．rest your wrists on something

D．keep your elbows as high as the keyboard

3.Your eyes and hands will be safe if __________.

A．you work near a window

B．you often take a rest from working

C．you use a keyboard for a long time

D．the window is behind you

4.It is good for your back and neck if you sit __________.

A．in the right way

B．for many hours

C．with the screen below your eyes

D．with your back leaning forward

5.What would be the best title for the passage?

A．How to protect your eyes

B．How to protect your hands and wrists

C．How to use a computer safely

D．How to protect your back

 

Every object has weight. But the center of its weight is not always in the middle of the object. If the top of an object is heavier than its bottom, it will fall over easily. We say that its center of gravity is high. But if the bottom is heavier, it won’t fall easily. Then we say that its center of gravity is low.

Look at the first picture. This empty box must fall over, because its center of gravity (C) is not above the line of its bottom (AB).

Now look at the second picture. There is some heavy iron in the bottom of this box. It will not fall, because its center of gravity is above its bottom.

1.If the bottom of an object is ______ its top, it will fall over easily.

A. lighter than　　 B. heavier than　　 C. no heavier than　　  D. as heavy as

2.Please point out which box will not fall.

3.The main idea of the passage is _________.

A. why things fall over　　　　         B. a low center of gravity

C. a high center of gravity　　             D. that everything has weight

 

The Internet, mobile phones and Ipads are part of our lives now. Technology is greatly affecting all ways of our lives, from the ways we work to the ways we play. And it even causes a number of social problems such as cloning humans.

　　We have had lots of technology and it has changed our lives a lot. There is no doubt that humans will continue to use more and more technology. Here are some examples of modern technology that will change our ideas and will affect our lives greatly.

　　Global positioning system (GPS) (全球定位系统)

　　It’s a system that uses radio signals from satellites to show exact(精确地) information. It tells you where the user is on the earth in all weather conditions. It’s made up of three parts: satellites, control equipments (设备) on land and receivers.

　　Space Technology

　　Russian and American scientists have worked together for the international Space Station (ISS) for a long time. They hope the ISS will provide a long-lasting lab. Such a lab will bring humans limitless(无限的) advantages. It’s even hoped that one day space technology will take humans to their new houses in space.

Underwater Robot

Hercules is a kind of underwater robot with some high technology equipments. It will be used to search for ancient ships which were destroyed into the deep sea during their journey long ago.

The world is changing so quickly that it’s hard for us to catch up with all the new inventions because they seem to come out every month. It’s important for us to learn about new technology and the role that it plays in our lives. So we should be willing to accept modern technology, or we will fall behind the times.

1.______ can tell you where the user is on the earth exactly.

A．Satellites                              B．Receivers

C．Global Positioning System                 D．Underwater Robot

2.According to the passage, which is NOT true about the ISS?

A．It has carried people to other planets.

B．It will provide a long-lasting lab for us.

C．Russian and American are working for it.

D．Humans will get a lot of advantages from it.

3.Hercules is used to ______.

A．save lives in the sea                     B．take picture in the sea

C．repair the broken ships                   D．look for the ancient ships in the sea

4.From the passage, we know that ______.

A．the use of GPS is affected by the weather conditions

B．it’s very important for us to learn about new technology

C．it’s easy for us to catch up with all the new inventions

D．technology brings us many advantages such as cloning humans

5.What is the purpose of the passage?

A．To help us study some new technology.

B．To tell us technology is changing the world.

C．To help solve the problems that technology causes.

D．To remind us the advantages of technology are limitless.