题目内容

Have you ever rubbed your hands together when they get cold? Why do we do that? We do that for friction. Friction happens when two things that aren’t very smooth (光滑的) rub together to make heat energy. The faster you rub two things together, the more friction you can make. Let’s discover friction!

WHAT YOU’LL NEED:
★Soap                ★Water           ★Your hands
WHAT TO DO:
★Make sure your hands are dry.
★Rub your hands together until you feel the heat of your hands.
★Now, use soap and water to get your hands very slippery (滑的).
★Try to make friction happen while your hands are slippery.
★Please write down what has happened.
LET’S TALK!
Friction is an energy that happens when two things rub together. When friction happens, it makes heat! When your hands are slippery, they won’t make very much friction and your hands won’t get so hot.
DID YOU KNOW?
★Friction happens when you stop your fast running bike.
★Ancient people made fires by rubbing two pieces of wood together. Friction happened though they didn’t know it. ___  __?         Friction is everywhere. Have you ever noticed situations where friction is happening? If not, ask your parents to take you out in a car. If it is not hot, touch the tires (轮胎) of the car before and after a short drive to see how much warmer they get from friction.
小题1:You’d better make your hands ______ to get heat when you rub them.
A. slippery                 B. dry                  C. wet    
小题2:The word “friction” in the first paragraph means “______”.
A. 摩擦                     B. 震动                 C. 膨胀 
小题3:We can know from the passage that it’s a ______ experiment.
A. physics                  B. chemistry                C. biology
小题4:The topic of the last column (栏目) is ______
A. THINK IT OVER!           B. WHAT HAPPENED?       C. WORK WITH PARENTS.
小题5:The main idea of the passage is ______.
A. how to discover friction     B. how to rub your hands       C. how to make fires by rubbing   

小题1:B
小题2:A
小题3:A
小题4:C
小题5:A

试题分析：本文是介绍摩擦是怎么产生的，摩擦产生的条件，摩擦产生了什么能量，以及日常生活中一些跟摩擦有关系的现象。
小题1:细节理解题。slippery滑的，dry干燥的，wet湿的，根据原文Make sure your hands are dry.Rub your hands together until you feel the heat of your hands.要先确定你的手是干燥的，然后把两个手放在一起摩擦直到你感觉到手热。故选B。
小题2:词义猜测题。根据原文Friction happens when two things that aren’t very smooth rub together to make heat energy.当两个不光滑的东西搓在一起产生热量，就是摩擦。故选A。
小题3:细节理解题。通过阅读可以知道摩擦是一种物理反应。故选A。
小题4:细节理解题。根据原文If not, ask your parents to take you out in a car.可知主题是跟父母一起共事，故选C。
小题5:细节理解题。根据原文Let’s discover friction!可知文章的主题是如何产生摩擦。故选A。
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The sun gives energy and the earth receives the sun’s energy. The way the earth interacts with the sun’s energy can be displayed in a picture called the earth’s energy budget（预算）. It displays the sun’s energy that reaches us and how much of that energy is taken in and how much is thrown back by the earth and its air. Once the energy reaches the earth, some of it is taken by land and oceans. The amount of energy that is taken in influences the temperatures. The energy that is not taken in is thrown back to space.
Generally, the amount of energy coming in is equal to the amount of energy going out. So, we say the earth’s energy budget is balanced. If more energy was coming in than was going out, the earth’s temperature would increase. On the other hand, if too much energy is thrown back, and not taken in, we would see the earth’s temperature dropping.
Of all of the sun’s energy that hits the earth, about 67% is taken in by the land, oceans, air and clouds and about 33% is thrown back into space.
小题1:The picture above shows us how ________ hits the earth.
A. the high temperature         B. the heavy rain               C. the sun’s energy
小题2:In the 2nd paragraph, the underlined phrase “equal to ” means “______”.
A. less than                    B. the same as              C. more than
小题3:Picture ______ shows us the main idea of the last paragraph.

A.       B.      C.

小题4:If too much energy is thrown back, we will feel ______on the earth.
A. cold                     B. hot                      C. warm
小题5:The amount of energy that is _______ influences the temperatures.
A. well balanced               
B. thrown back                 
C. taken in
Smartphone ,poor sight
Look around and you’ll see people busy on their smartphones. Smartphones do make our lives easier . But have you ever thought about what they mean to you eyes?
According to a study ,half of British people own smartphones and they spend an average of two hours a day using them . There has been a 35% increase in the number of people in the UK who suffer from shortsightedness since smartphones were introduced there in 1997.
Staring at smartphones for long time gives you dry eyes. When looking at something in the distance ,your eyes automatically blink a certain number of times. However ,when you look at things closer  to your face ,the blinking slows down . This reduces the amount of tears and causes discomfort in your eyes. Another bad habit is using  smartphones in dark rooms before going to sleep . If you look at a bright screen while your pupils become larger ,too much light enters your eyes. This can do harm to the eyes and cause a disease called glaucoma.
While you’re probably not going to stop using to your smartphone,there are a few things you can do to protect your eyes. Hold  your phone at least 30 continues away from your eyes when using it. Take a break every hour and try the following :look at something at least five meters from you and then focus on the tip of your nose. Repeat this several times. It should reduce the discomfort in your eyes.
阅读下列短文，根据短文中的信息完成文后表格。在答题卡标有题号的横线上，写出空缺处所填单词的正确形式。（每空一词）
We eat food to get energy, so we should eat when we feel hungry. But do we really eat only when we are hungry? No, we sometimes eat even when we’re not hungry, and this causes overeating ----eating too much. But overeating can do a lot of harm , as it can cause obesity（肥胖）that can cause heart problems and other illnesses.
There are many common reasons that make us eat too much.
Meeting friends may be good for our social life, but it can also be one of the main reasons for overeating. We usually pay no attention to our health when we meet with friends.
Moods such as anger, sadness, happiness ,fear are the most common ones that make us eat food to help us feel better .
Busy lifestyles can have an effect on our eating habits .We start eating too quickly just to save time , as a result ,we eat more than our body’s requirement . When we eat meals or snacks too fast, our brain takes some time to realize that it’s full, and of course it results in overeating.
Temperature plays a very important role in deciding our food habitat In winters, we usually have warm or hot drinks like coffee, tea, hot chocolate and heavy meals to keep ourselves warm . In summers , we have ice dreams ,desserts and other drinks .These foods with the regular food add to calorie and lead to overeating .
Supermarkets have lots of attractive offers to get us to buy things that we may or may not need .There is no doubt we love eating and when we are served with our favourite food , we act like we have never seen food before .
We have always been taught to finish everything that is on the plate .So, even when we start feeling full , we keep on eating till our plate is empty or till we stop feeling guilty about wasting food .
How to control how much you put in your stomach ? here are some ways .
Use smaller plates and tall, skinny glasses. It seems that there is more food on the plate and more to drink in the glass. Smaller serving containers（容器）help stop you from putting much food and drink .
Make the sweets and other snacks out of reach . Get the candy dish off your desk and set out a bowl of fruit instead .
Don’t overeat
___小题1:_that is caused by overeating
Overeating can cause obesity and some illnesses.
Common ___小题2:___ of overeating
*When we eat with our friends, we eat too much ___小题3:___paying attention to our health.
* When we __小题4:____ from different moods, we often turn to food to feel better.
* Busy lifestyles can __小题5:____our eating habits. We eat too fast to save time.
* Because of temperatures in different __小题6:_____, we have some food that adds to calorie.
* Attractive offers in the supermarkets make us buy and eat our ___小题7:____food.
* We don’t __小题8:____ eating until the plate is empty.
__小题9:___to control overeating
*Don’t use __小题10:_____ serving containers when you eat food or drink.
*Don’t make it easy to eat the unhealthy food.
In the most southern part of our planet, there’s a place that’s covered with snow and ice all year round. But it has the clearest and cleanest air. Amazingly, in this place, the sun sometimes hangs even in the midnight sky. This place is Antarctica (南极洲): the coldest, windiest and harshest (恶劣的) place on the Earth.

As the world’s least-known place, Antarctica is of great interest to scientists around the world. In 1983, China joined the Antarctic Treaty (《南极条约》). The treaty made Antarctica a peaceful place for member countries to do scientific research. During 30 years, China has sent many scientists to Antarctica. They mostly look at the resources under the icy land and do research about climate change and marine (海洋的) biology.
Antarctica is a place with fantastic views. However, life there is very hard. Food is one of the biggest problems. Frozen (速冻) food which can be heated easily is people’s daily food. Fresh vegetables are hard to grow in the cold weather. Therefore, scientists often eat dried or canned vegetables.
Sleep is also troublesome. In Antarctica, summer lasts from November to March. During this period, Antarctica points to the sun and receives sunlight 24 hours a day. In order to get some sleep, scientists cover the windows with black plastic cloth to create “night”.
Working in Antarctica is dangerous, especially when meeting gale-force (七级以上的) winds. Sometimes the wind is even stronger than a typhoon. It can easily blow people away. So there are ropes that connect buildings of some research stations. People can hold these ropes to keep their balance in forceful winds.
What’s more, communicating with others is difficult. Without cables and Internet in some research stations, two-way radios are the only tools to communicate. If people want to say hello to friends and relatives, they can use satellite phones.
Although it is challenging to work in Antarctica, scientists’ passion to learn about this mysterious land will never end. It is hopeful that one day they will step every corner of this icy land.
小题1:From Paragraph 1, we learn that the Antarctica ______.
A．is covered with snow and ice
B．rains heavily from time to time
C．has little wind most of the time
D．has sunshine during every night
小题2:Scientists from China go to Antarctica to _____.
A．find out ways to control water pollution
B．research climate change and marine biology
C．grow plants and vegetables in special condition
D．stop the hunters from killing the marine biology
小题3:In order to sleep well in Antarctica, the scientists have to _____.
A．wear more clothes to keep warm
B．cover the windows with black cloth
C．connect research stations with ropes
D．eat more fried and canned vegetables
小题4:We can replace (替换) the underlined word passion in the last paragraph with       .
A．strong love
B．full preparation
C．pleasant introduction
D．amazing imagination
小题5:The passage is mainly about       .
A．view of the Antarctica
B．exploring the Antarctica
C．how to survive in the Antarctica
D．climate changes of the Antarctica
The sun is a huge, hot and bright star. It is important because without it there would be no life on the earth. The sun gives us light and heat.
All living things depend on the sun for their growth. Plants need light and heat to grow. They use the light from the sun to make food. But we human beings cannot make food by our own bodies from the sun. All the food we eat comes from plants in a food chain(链) . And the food chain starts with the sun . For example.
sun —→ potatoes  —→ chips
sun  —→ corn  —→ hens  —→ eggs
sun—→ wheat  —→ bread
Animals need sunlight, too. Just like us, their food comes from plants in food chain, which begins with the sun. For example,
Sun → leaf → caterpilllar(毛虫) → bird
Sun → seaweed(海藻) → small fish → whale(鲸)
With the help of sunlight, we can see things during the day. Even when the sky is cloudy, the sunlight is very strong and it shines through the clouds. If there was no sun, it would be dark all the time.
小题1:The sun is a           star.
A. huge, cold and bright        B. huge, hot and bright       C. small, warm and bright       
小题2:What are the two main things the sun gives us?
A. Light and heat.             B. Heat and eggs.           C. Corn and light.              
小题3:From the passage we learn that         .
A. when the sky is cloudy, there is no sunlight at all                 
B. without the sun there will be no life on the earth
C. we human beings can make food by our own bodies
小题4:All the food we eat comes from          in a food chain. And the food chain stars with the         .
A. plants; earth       B. plants; sun            C. animals; star      
小题5:Which is the best title (标题) for this passage?
A. Plants need heat and light to grow
B. All living things depend on the sun for their growth
C. The sun is very important
通过下列短文，掌握其大意，然后从短文后各题所给出的四个选项中选择最佳的一项，并将答题卡内相应的字母标号涂黑。
Is your schoolbag too heavy? The e-schoolbag will help you. It is said         e-schoolbags are going to be brought into       in Chinese middle schools soon.
Heavy schoolbags have been a serious       for a long time. But the e-schoolbag will     .        e-schoolbag is      lighter than a usual schoolbag. Perhaps, the e-schoolbag should be       an e-textbook. It is a small computer for students. It is as       as a usual book,       it can still have all the things for study,     textbooks, exercise books and so on which can be made       chips(芯片) like stamps. The students can read the text page by page on the screen,        notes, or even send e-mails to their teachers. They only need to       the right chip into the e-schoolbag. Then they can use it.
Some people say       e-textbooks can be      broken, while others say it is not good for eyes.  But only time will tell.
小题1:
A．whatB．thatC．whichD．whose
小题2:
A．useB．usefulC．usedD．to use
小题3:
A．ideaB．problemC．questionD．thought
小题4:
A．work it outB．work out itC．work outD．work them out
小题5:
A．AnB．TheC．/D．A
小题6:
A．veryB．muchC．tooD．so
小题7:
A．callB．callsC．calledD．calling
小题8:
A．smallB．smallerC．smallestD．most small
小题9:
A．andB．asC．orD．but
小题10:
A．exampleB．such asC．such likeD．for example
小题11:
A．intoB．fromC．upD．of
小题12:
A．takeB．makeC．to takeD．to make
小题13:
A．bringB．getC．takeD．put
小题14:
A．ifB．whatC．thatD．which
小题15:
A．easyB．easilyC．most easilyD．easier
Have you seen Avatar？It’s a popular movie this year. It is three-dimensional(3D), so you may have to wear a special pair of glasses to see it. The 3D glasses make the images(图像) from the movie look like they are coming straight at you.
More and more 3D movies are coming to theaters. 3D TV sets have been produced in Japan now. Three-dimensional technology can make TV and movies more exciting. But people with eye problems may get headaches if they spend too much time watching 3D movies.
When we look at an object(物体), each eye sees it at a different angle(角度). Our eyes send the two images to our brain(大脑), and the brain puts them together. That’s how we see depth(深度). So when we watch a 3D movie, one film projector(投影机) projects a left eye image and the other projects a right eye image. 3D glasses allow us to see a different image in each eye.
There are a lot of people walking around with very less serious eye problems. Under normal situations, the brain can adjust to their eyes so they can see things normally.
But when they are watching a 3D movie, the images projected to their eyes can’t be put together by their brain. So the brain needs to work harder at reading the images. That makes it easier for these people to get headaches.
Dr John Hagan, an eye doctor in Kansas City, said some people who do not see depth normally cannot see in 3D at all.
小题1:When people want to watch a three-dimensional movie, they need          .
A. a ticket                  B. a pair of 3D glasses             C. an earphone
小题2:Three-dimensional technology uses         film projector(s) to project one movie at the same time.
A. one                     B. two                         C. three
小题3:According to the passage, if we look at an object by only one eye, we can’t judge the       excatly.
A. image                   B. angle                         C. depth
小题4:Which statement is TRUE according to the passage?
A. In the near future, people can enjoy 3D movie by watching TV at home.
B. Whenever you wear a 3D glasses, you can see objects more clearly.
C. People who have something wrong with their brain can’t read the images of 3D movie.
小题5:The main idea of this passage is            .
A. how to use 3D glasses to watch a 3D movie.    
B. 3D glasses make the movie seem alive
C. not everybody can enjoy 3D movies.
The H1Nl virus has been spreading world-wide，it is important for us to know how to control it．Please pay attention to the following points：
1．Don't touch your face．Above all，keep your hands away from your eyes，mouth and nose，all of which serve pathways(途径) for the viruses(病毒) to enter your body．
2．Wash your hands．If you have to touch your face，wash your hands，getting under the fingernails for 20 to 30 seconds with hot soap and water before．Soaps with surfactants(表面活性剂) can deal with flu viruses．
3．Cover your nose and mouth．When someone sneezes or coughs，liquid(液体) drops with flu viruses as far as three feet through the air and land on your nose and mouth，so it's best to keep at least an arm's length distance when talking to someone who shows signs of infection(感染)．In order to protect others，cover your mouth and nose with a tissue(纸巾) when you cough or sneeze，and clean your hands afterward．Viruses can live for hours，or even longer when on the skin or other surfaces such as keyboards．
4．Consider buying a mask in case you need it in the future．Some research suggests that masks reduce the risk of getting the flu viruses by as much as 80%．But it also suggests that if you don't wash hands，the mask doesn't work well．So wash your hands and use the mask，especially wearing face masks in crowded places is also useful．
根据短文内容，选择最佳答案。
小题1:The article mainly tells ________．
A．the H1N1 virus has been spreading world-wide
B．how to control the H1N1 virus
C．cover your nose and mouth
D．everyone should buy a mask in the future
小题2:How does the viruses enter your body easily?
A．Get though your mouth．B．Get though your nose．
C．Get though your eyes．D．All of the above．
小题3:What can we do with the flu viruses?
A．Water．B．Masks．C．Soaps with surfactants．D．Tissues．
小题4:How long can the viruses live on the skin or other surfaces such as keyboards?
A．For an hour．B．For several hours．C．For two weeks．D．For a year．
小题5:Which of the statements is Not True?
A．Wash your hands before meals．
B．When you cough or sneeze，you should cover your mouth and nose with a tissue．
C．You shouldn't often touch your mouth，eyes and nose．
D．When you put a mask，you can often go to the crowded places．

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