题目
题型：不详难度：来源：
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
答案
小题1:B
小题2:A
小题3:A
小题4:C
小题5:A
解析
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。
核心考点
试题【Have you ever rubbed your hands together when they get cold? Why do we do that? 】；主要考察你对科普环保类等知识点的理解。[详细]
举一反三
Canada is a big country with six time zones. In the west, it is four a.m., and everyone is asleep, but in Halifax on the east coast it is eight o"clock and people are having breakfast. It is a cold Friday morning in November, and the temperature is ten degrees below zero Centigrade(度).
Argentina 9:00 a.m.
In Buenos Aires, the capital of Argentina, it is nine a.m. on a warm summer morning, and people are starting work or school. November is a summer month in Argentina because it is in the southern hemisphere(半球).
Scotland 12:00 noon
Scotland is part of the United Kingdom. The capital of Scotland is Edinburgh, and the capital of the UK is London. It is twelve noon, or midday, in Edinburgh. Children are having lessons, but they are looking forward to the weekend because there is no school on Saturday and Sunday.
Egypt 2:00 p.m.
Friday is already the weekend in Egypt. Friday is a special day for Muslims, so schools, offices and shops are closed in all Arab countries. So now, at two p.m., most people in Egypt are having lunch with their families.
Japan 9:00 p.m.
Japan is seven hours ahead of Egypt, so it is already Friday evening there. The weekend is beginning. Most people are out with friends or watching television or playing computer games.
New Zealand 12:00 midnight
It is late on Friday night, so most people are asleep. Now Saturday morning is arriving. It is morning in Canada too, but that is Friday morning!
小题1:In eastern Canada, the time is ______ than that in western Canada.
A. four and a half hours later B. four hours earlier C. three hours earlier
小题2:While Canadian children in Halifax are having breakfast, Argentinean children are ______.
A. sleeping B. going home C. having classes
小题3:It’s midday in the capital of ______ when it’s 9:00 a.m. in the capital of Argentina.
A. Japan B. Scotland C. New Zealand
小题4:Now it’s 2:00 p.m. and you are in Egypt. It’s ______ for you to call a friend in New Zealand.
A. impolite B. polite C. normal
小题5:If it’s 11:15 p.m. in Japan, it’s ______ in New Zealand.
A. 2:15 a.m. B. 2:15 p.m. C. 1:15 p.m.
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 50cm 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(反射) on 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 rules: ①Rest your wrists on something. ②Keep your elbows at the same height as the keyboard. ③Stop sometimes 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 be in front of your eyes. Your forearms, wrists, hands and the upper part of your legs should all the 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 neck.
小题1:A computer screen may injure your eyes if __________.
A. you sit 60cm away
B. your eyes are too close to it
C. the window is on your left or right
小题2:Hand and wrist injuries are caused when you __________.
A. move in the same way again and again
B. rest your wrists on something
C. keep your elbows as high as the keyboard
小题3:When using a computer, your eyes and hands will be safe if you __________.
A. work near a window
B. work for a long time
C. take rests at times
小题4:It is good for your back and neck if you sit __________.
A. for many hours
B. in the right way
C. with the screen below your eyes
小题5:What would be the best title for the text?
A. How to Use a Computer Safely
B. How to Keep your Hands and Wrists Safe
C. How to Protect your Eyes and your Back
But things are changing. High costs, unusual educational needs and long start-up times are no longer an obstacle(障碍) to space exploration. The scientists have developed a new type of tiny, inexpensive earth-orbiting(轨道) satellite.
So far, college students have built and launched(发射) several cube-shaped satellites, or CubeSats. At least 15 more are ready to go. Those already in orbit take pictures, collect information and send it back to the earth, just as regular satellites do.
But you might not even have to wait until you get to college to start designing and building your own satellite. A new program called KatySat aims to get teenagers to take part in. When kids understand what satellites can do, the kinds of ideas they’ll come up with may be countless.
Education isn’t the only aim of CubeSats because these tiny, technology-filled boxes are inexpensive to build and can be put together quickly, they’re perfect for testing new technologies that might one day be used on major space tasks.
The biggest challenge now is to find ways to bring the satellites back to the earth after a year or two. Or space junk could gradually increase because CubeSats become more popular.
Nowadays, college and high school students are getting a chance to learn what it takes to explore in space. Someday—perhaps a lot sooner that you imaging—you might get to design, build and launch your own satellite. If you do, you’re sure to have fun. And you might also get crazy about science for life.
小题1:Building a traditional satellite __________.
A. costs $250,000
B. needs college students
C. takes quite a long time
小题2:Compared with the traditional ones, the new satellites __________.
A. need long start-up times
B. are cheap and small-sized
C. collect more junk in orbit
小题3:The underlined word “countless” in Paragraph 4 probably means “__________”.
A. 无用的 B. 无价值的 C. 无数的
小题4:According to the passage, which of the following is true?
A. CubeSats could possibly cause pollution in space.
B. Scientists designed CubeSats for kids to play with.
C. Students can’t design satellites without college education.
小题5:The purpose of the author writing the passage is __________.
A. to tell us that satellite technology can also be learned by kids
B. to show that high technology brings a big change in kids’ life
C. to tell us that kids must study hard to learn satellite technology
Tea mainly in the area south of the Yangtze River, in the provinces of Zhejiang, Jiangxi and Fujian, because of the good and rich soil there. Longjing, Wulong, Pu’er and Tieguanyin are all kinds of tea.
Over the past centuries, Chinese people have their unique tea culture, which includes tea planting, tea-leaf picking, tea making, and tea drinking and so on. Tea as well as coffee a popular topic which is often mentioned in dances, songs, poems and novels.
| 小题1: |
|
| 小题2: |
|
| 小题3: |
|
| 小题4: |
|
| 小题5: |
|
| 小题6: |
|
| 小题7: |
|
| 小题8: |
|
| 小题9: |
|
| 小题10: |
|
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 |
| 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 |
| 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 |
| A．strong love |
| B．full preparation |
| C．pleasant introduction |
| D．amazing imagination |
| A．view of the Antarctica |
| B．exploring the Antarctica |
| C．how to survive in the Antarctica |
| D．climate changes of the Antarctica |
最新试题
- 1已知集合A={x|x2＞1}，B={x|log2x＞0}，则A∩B=[ ]A.{x|x＜-1}B.{x|x＞0}
- 2已知函数f(x)=logax+1x-1．（Ⅰ）求f（x）的定义域；（Ⅱ）判断f（x）的奇偶性并证明；（Ⅲ）求不等式f（x
- 3被雨水淋湿的自行车必须先用干布擦净后，再用带油布的擦而不能直接用带油的布擦拭，原因是[ ]A.这样不能使自行车更
- 4该图是我国某城市居民2009年收入构成一览表：内容工资、薪金收入房屋、土地等收入国债收入股票收益利息收入比例（%）403
- 5下列关于明治维新的叙述错误的是[ ]A．明治政府在“富国强兵，殖产兴业，文明开化”的口号下进行的改革B．明治天皇
- 6设则是“”成立的 ( )A．充分必要条件 B．充分不必要条件C．必要不充分条件D．既非充分也非必要条件
- 7在直角坐标系中，将点P（3，6）向左平移4个单位长度，再向下平移8个单位长度后，得到的点位于（ ）A．第一象限B．第二
- 8近年来，一些文艺创作特别是历史题材的创作中，出现了一些不良倾向。表现之一是以偶然性、模糊性、荒诞性去解构历史，随心所欲地
- 9（5分）根据原子结构的知识和下图的信息填空：（1）甲图中①代表的元素符号是 ，乙图中所示元素原子的核电荷数是
- 10如图所示，绳子一端固定，另一端栓一个质量为m的小球，现让小球从A点无初速地释放，下落过程中经过B点最后到达最低点C，则小
热门考点
- 1从已有3个红球、2个白球的袋中任取3个球，则所取的3个球中至少有1个白球的概率是（ ）A．110B．310C．35D．
- 2在用插针法测定玻璃砖折射率的实验中，甲、乙、丙三位同学在纸上画出的界面aa′、bb′与玻璃砖位置的关系分别如图中①②③所
- 3完形填空。 There are times when people are so tired that they
- 4我国公民享有广泛而真实的权利。青少年在行使自己的权利时 [ ]①必须在法律允许的范围内行使②必须在老师或家长同
- 5已知函数且，另外两个零点可分别作为一个椭圆、一双曲线的离心率，则的取值范围是 .
- 6So carelessly _____ that he almost killed himself.A．he drive
- 7（1）金属锰可以用四氧化三锰为原料通过铝热法来制备。试写出配平的化学方程式。（2）CS2是一种有恶臭的液体，把它滴入硫酸
- 8在我国，国家的一切权力属于（ ）A．人民B．公民C．工人D．农民
- 9下列各句中，没有语病的一项是（3分）A．信息数字化对个人生活发生了十分直接的影响，如果名字里用了一个计算机字库里没有的字
- 10阅读理解。 Should parents ever hit their children? Resea