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It’s there, but it has no weight, no colour, and you can’t smell it. You can’t see it, but it’s working everywhere in our modern world. Don’t try to touch it! It’s dangerous. It has always existed, but humans learned about it only 500 years ago.
What is it? Electricity. It’s powerful and mysterious. Thanks to electricity, you can flick a switch(开关)and have light. Watched a good TV show lately? You couldn’t do that without electricity. We cook our food, heat our homes and run our computers using electricity. But what is it, really?
Here is a simple description. Everything in the world is made of atoms (原子). Atoms are small. You can fit millions of them on the head of a pin. In every atom, there are electrons (电子), protons (质子) and neutrons (中子). In some atoms, it is possible to move electrons easily from one atom to another. As the electrons move, a current(电流) is created. This is electricity.
Don’t worry if you don’t understand it fully. Just remember that electricity is the result of the movement of electrons. As the electrons move, they create a strong electric charge.
There are many ways to generate electricity. A machine called a generator spins(旋转) rapidly. Water and wind can make a generator spin. So can motors fuelled by oil. As the generator spins, the electrons begin to move. As they move, they create an electric current. Power lines (电线) are built from generators to carry this current to places where people can use it. Along your street, power lines bring electricity right to your door. A wire runs into your house. More wires inside your house are attached to the plugs. Plug in your lamp, the electricity lights up the bulb, and you have light!
It takes a lot of energy to make electricity. Oil is one of the main fuels(燃料) used to power electric generators. Another common fuel is coal. Our planet is running out of these resources, and using them creates a lot of pollution.
In the future, most electricity will be produced using the sun and wind. But for now, be careful about how much electricity you use. Don’t forget to turn off the lights when you leave a room. Every little bit helps.
1.The writer mentions atoms in the third paragraph to .
A.show the relationship between electricity and atoms
B.explain what the electricity is
C.tell us everything in the world is made of atoms
D.describe how the electrons move
2.The underlined word “generate” in Paragraph 5 probably means .
A.move B.understand C.produce D.use
3.According to the passage, the writer probably agrees .
A.it’s very easy to make electricity
B.oil and coal are pollution
C.most electricity is produced by sun and wind now
D.everyone should do his best to save electricity
4.What might be the best title for the passage?
A.How to make electricity.
B.How electricity helps us.
C.Electricity — A Natural Force.
D.Save the energy; Save the world.
七年级英语阅读单选困难题查看答案及解析
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A:Excuse me.1.
B:No, but there is one on Nanjing Street. And it is a good place to have fun.You can take a taxi to get to Nanjing Street.
A: 2.?
B: Yes, you can. 3..
A:Well, is there a bank near the park?
B: Yes.4..There is a supermarket on the corner.Then pass the supermarket, and you can see a small restaurant. 5..
A: Thank you very much.
B: 6..
A. You are welcome.
B. Is there a park near here?
C. On your left is a bank.
D. The hotel is in front of the park.
E. Just go down Nanjing Street and turn right
F .Can I find a hotel near the park
七年级英语阅读单选中等难度题查看答案及解析
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1.
Back in the 1980s, researchers found that jumping on a trampoline was a good way to help people build up their physical strength. Actually, trampolining has many advantages. Let me show you some：
2.
If you would like to start trampolining, you may first need to ask a doctor to make sure it's a safe activity for you. It's easy to find an inexpensive trampoline, but it should be wellmade and strong enough to support your weight.
3.
Here are a few exercises for beginners：
•High Knee Lift. Raise one knee at a time. Lift your knee higher than you usually do when you are running.
•4.
•Tuck Jump. At the top of your jump, bring the knees to the chest, with the arms holding the legs.
5.
Word Bank
Trampoline 蹦床 chest 胸
A.There are many more exercises you can try. Happy trampolining!
B.Have you ever jumped on a trampoline? Today many people use it for exercise.
C.Star Jump. Jump into the air and spread your arms and legs into a star shape. As you gain more confidence, practice more difficult levels.
D.To avoid accidents, some trampolines have a safety net around them. Remember: whenever you are on a trampoline, be careful not to jump near the edge of it.
E.It helps bones grow and improves your balance. It helps your body get rid of harmful things. Trampolining has benefits similar to those of running, but without too much stress on knees.
七年级英语补全短文5选5中等难度题查看答案及解析
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There ______ some milk and eggs on it, but he can’t reach(够到) them.
A. has B. have C. is D. are
七年级英语单项填空中等难度题查看答案及解析
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— What can you see in the picture?
— There a car and two bikes in it.
A．is B．has C．are D．have
七年级英语单项填空中等难度题查看答案及解析
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— Is the ID card ______?
—No, it’s not. Grace is there. You can go and ask ______.
A.yours; her B.your; hers C.your; me
七年级英语单选题中等难度题查看答案及解析
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You must think a computer is the best thing in the world, right? You must think it works at a super speed and can do everything? Well, it's not! In fact, the brain is much more powerful than any super computer! Think about when a glass is just about to fall off the table. Your brain controls everything that you need to do to save that glass from falling. First your eyes check out what's going on, then tell your brain, and your brain decides how quickly you need to react(反应), and then your muscles(肌肉) go into action. That is just from your brain. No computer could ever come close to that!
The brain weighs just 3 pounds, but it controls everything you do from thinking, learning, feeling even to breathing and your heart beating. Even though the brain is just 2% of your body weight, it uses around 20% of all your energy in your body. That is a lot for such a small organ(器官). There are about 100 billion tiny, tiny little cells(细胞) in your brain. There are so many that it would take you over 3, 000 years to count them all!
Your brain stops growing when you're 18, but it actually keeps on developing and learning new things. So your parents are really super smart! You won't be able to fool them! Believe it or not, your brain NEVER stops working. Even during sleeping, the brain works for longterm memory establishment. It is realized that the brain is the second organ in the body as the heart that never stops during human lives.
So everyone should be proud of such a gift of nature.
1.From the first paragraph we know that ________.
A.eyes and muscles react quickly
B.the brain controls everything in your body
C.the computer is the best thing in the world
D.the brain is more powerful than any computer
2.Which of the following is TRUE according to the passage?
A.The brain doesn't work during sleeping.
B.The brain is the only organ that never stops.
C.The brain keeps growing during human lives.
D.The brain keeps on developing during human lives.
3.In which magazine can the passage be found most probably?
A.Business Weekly B.Medicine C.Science D.Sports
4.The underlined word“establishment”in the passage means“________” in Chinese.
A.储存 B.形成 C.空缺 D.建立
5.The best title for this passage is “________”．
A.A Powerful Organ—Human Brain
B.How Computers Work
C.Scientists' Research
D.Human Being's Activities
七年级英语阅读单选中等难度题查看答案及解析
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路子宽为救父而增重
We have heard a lot of stories about parents trying their best to save their children's lives. But today I will tell you a_____ story.
Lu Zikuan is an 11yearold boy who studies at school in Huixian county, Central China's Henan Province. But he has_____ a task to save his father's life in an unexpected way—by eating as much as he possibly can. Maybe many people think the_____ is simple. But in fact, becoming fat isn't easy in such a short time.
The father needs a bone marrow transplant(骨髓移植), and the hospital will only do it_____ the donor(捐赠者) is in a certain weight (45 kilograms). The doctor said that the heavier the weight is, the_____ the operation will be.
Lu Zikuan is the only one that can match his father's bone marrow in the family. He is now gaining weight as_____ as possible to meet the requirement. Every day, he must eat a lot of food. It_____ him always have a stomachache. “Even if it hurts, I'll still eat，” Lu said. “Our_____ can't bear(承受) the loss of my dad.”
He has increased quickly to 48 kg_____ 30 kg since March, when the bone marrow from the boy successfully matched that of his father. His aim is to______ 50 kg, as agreed with his father. And this was his wish on this year's International Children's Day on June 1.
1.A.common B.similar C.happy D.different
2.A.given up B.gotten up C.taken up D.made up
3.A.health B.task C.work D.plan
4.A.although B.since C.if D.until
5.A.better B.worse C.richer D.poorer
6.A.slowly B.luckily C.suddenly D.quickly
7.A.makes B.means C.shows D.points
8.A.friend B.classmate C.family D.student
9.A.for B.from C.about D.with
10.A.catch B.reach C.teach D.match
七年级英语完型填空中等难度题查看答案及解析
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Everyone needs friends. But how do you find real friendship and keep it?
The Care and Keeping of Friends, written by American writer Sally Seamans, tells young students some smart ways to find friends.
Sally says finding friendship is just like planting a tree. You plant the seed and take care of it to make it grow.
First, you should choose a friend. What makes a good friend? It is not because a person has money or a good look. A good friend should be kind and patient. For example, if you have a bad day, a good friend should listen to your complaints and do his or her best to help. To make a friend, you cannot be too shy. You should make each other happy and share your life.
But things cannot always be happy. Even the best friends have fights. What should you do when you have a fight with your friend? You have to talk to him or her. When there is no one around, have an honest talk. If he or she doesn't want to talk, you could write a letter.
Sally says there are three steps to be friends again: tell him or her how you are feeling, say what your friend has done wrong, and explain why you did this or that. The book also gives advice on some small but important things like celebrating your friend's success. Even_if_you_haven't_had_a_best_friend_before,_you_can_start_to_think_of_having_one. Because the book tells that friendship is the most important thing in your life.
1题判断正误(T表示“正确”，F表示“错误”)；2题完成句子；3题简略回答问题；4题找出并写下全文的主题句；5题将文中画线句子译成汉语。
1.The Care and Keeping of Friends tells young students some smart ways to find friends.
2.In Sally's opinion, finding friendship is just like _________.
3.What kind of talk should you have after you fight with your friend?
__________________________________________________________
4.________________________________________________________
5.________________________________________________________
七年级英语多任务混合问题中等难度题查看答案及解析
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It may be difficult to start high school. Thinking about making new friends might make you feel nervous.1.You are going to school with a group of students of your age. Here are several suggestions for you to follow.
Forget your fear and just talk to someone.
It's easier said than done. But try to take a deep breath and find your voice. Don't be afraid to approach people.2.Sit in the middle of the classroom with many new friends around you as much as possible.
Join clubs.
Take part in afterclass activities that interest you. 3.If you don't join anything, you will be just going to class and then going home. Being in a club makes you more social.
Stay clean.
No one likes a bad smell that could knock someone over. Shower everyday, brush your teeth and wash your hair.4.
Be respectful of people's differences.
5.And everyone believes in different things. It is a good thing to have different friends with different opinions because you can share your own opinions with them.
A.Try to make friends in the clubs.
B.But don't worry, because you are not alone.
C.Everyone has his or her own opinion of the world.
D.You are supposed to make yourself look clean and tidy, whatever you wear.
E.Introduce yourself and start a conversation about something you have in common.
七年级英语补全短文5选5中等难度题查看答案及解析