How much do you know about Earth—the planet that we live on? Our knowledge of Earth has been developing since ancient times. However, many puzzles (谜) about Earth remain unsolved. Live Science has published a list of the eight biggest mysteries about Earth. Let’s look at some of them.
Where did water come from?
When it first came into being 4.5 billion years ago, Earth was a dry rock. So where did all of our water come from? Scientists think that it might have arrived in the form of ice by an asteroid (小行星) from outer space that hit our planet. But this idea has not been confirmed (证明) because there is very little related evidence(相关证据) to be studied.
What’s in the core (地核)?
Scientists used to study meteorites (陨石) as small examples of Earth, believing that Earth’s core was made of iron and nickel (镍). However, a later study in the 1950s proved this way to be wrong because it found that Earth would be too light to provide gravity (引力) if its core contained only iron and nickel. Today, scientists continue to bring forward different ideas, but none have been confirmed.
How was the moon born?
Scientists have found that the chemical compositions (成分) of Earth and the Moon are very similar. That suggests that the Moon actually came from Earth. For example, it could be a piece of Earth that separated when Earth hit another planet. It is also possible that when Earth first came into being, it spun (旋转) very fast and threw off enough molten (熔化的) rock to later form the Moon.
1. What’s the main idea of the passage?| A．How Earth came into being. |
| B．Where Earth’s water came from? |
| C．How the moon was formed? |
| D．Unexplained mysteries about Earth. |
| A．Earth’s water may come from ice that melted 4.5 billion years ago. |
| B．Earth’s water may come from a small planet that hit Earth. |
| C．We don’t know where water came from. |
| D．There is lots of evidence that tells us where water came from. |
| A．Check | B．Raise |
| C．Improve | D．Receive |
| A．Scientists used to believe Earth’s core was made of meteorites. |
| B．A study in the 1950s proved that Earth’s core is made of iron and nickel. |
| C．The moon and Earth are made of similar materials. |
| D．Three possibilities of where the Moon came from are mentioned. |
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【推荐1】Vicuna, a small town in the north of Chile, is a great place for watching stars all year round. Although it is near the sea, the cold, wet air from the coast does not bring clouds. Instead, dry winds from the desert keep the clouds away at night. In fact, the sky is so clear in Vicuna that it is possible to see many stars that can be seen only with advanced(先进的) instruments in other parts of the world.
In Vicuna, distant(遥远的) star systems such as Magellanic Clouds can be seen without the help of an instrument. That is why the town was chosen as the home of a number of sky observatories(天文台). One of them, the Mamalluca, is quite different from the typical observatories used by scientists. This observatory was built for tourists who like to look at the stars. During the year, Vicunas hotels accommodate thousands of tourists who come from all over the world to see the night sky as they have only seen it in books. The cloudless sky is clearly a moneymaker for the town, which plans to set up even more observatories. It was recently decided that building observatories would go on for another few years.
At one point, however, the town faced a serious problem. As the town grew, more streetlights were added, making it more and more difficult to see the stars at night. The town saved the night sky by building a new system of lights that lit up the streets without influencing the view of the sky.
1. What can we know from Paragraph One?| A．The sky in Vicuna is clear all year round. |
| B．Vicuna is a small town far from the ocean. |
| C．The wet air from the coast keep the clouds away. |
| D．We can see wonderful clouds in the sky over Vicuna. |
| A．建议 | B．控制 | C．容纳 | D．欢迎 |
| A．The old streetlights used lots of electricity. |
| B．The old streetlights made it hard to see the stars at night. |
| C．The new streetlights would make streets more beautiful. |
| D．The new streetlights would make the sky more beautiful. |
| A．Vicuna Has a Problem | B．The observatories in Vicuna |
| C．A Town to Watch the Stars | D．The new system of lights in Vicuna |
【推荐2】We have seen lots of science fiction movies about aliens (外星人). People travel to stars and even fight with aliens in the movies. But are there real aliens in the universe (宇宙)? Most of us think it is impossible, just like fairy tales. But the answer of some scientists is yes. So they have been searching for aliens in outer space for many years. They hope to find life signs of aliens.
Some scientists are used to using radio telescopes (望远镜) to search for aliens in space. In order to find aliens, they have worked hard for over half a century, but so far they have found nothing. Then some scientists guessed aliens might not want to connect us, but aliens could answer our messages. So some scientists sent radio signals into the universe. They hope one day they would be picked up by alien technology. These scientists want to prove (证明) that we are not alone in the universe.
But what should we do if the “alien phone” rings one day? Should we answer it? Stephen Hawking, the famous physicist, thught it could be dangerous to connect aliens. He said that the main purpose of aliens’ visit to the earth could be searching for our resources (资源). But other scientists think we have no need to worry. David Morrison, a NASA scientist, said, “If an alien radio signal reaches the earth from a planet thousands of light-years away, then they almost surely have solved all the problems we still have including the short of resources. Maybe they are much smarter than us, but why do they want to hurt us? I think we can try to connect them.”
1. ________ scientists believe there are aliens.| A．Few | B．All | C．Most | D．Some |
| A．50 years | B．more than 50 years | C．40 years | D．more than 100 years |
| A．are friendly | B．are dangerous | C．can’t be found | D．have been on the earth |
| A．we want to find aliens | B．aliens have many skills |
| C．we want to help aliens | D．aliens are much smarter than us |
| A．Ideas about aliens | B．Protect our earth | C．Stephen Hawking’s idea | D．How to find aliens |
【推荐3】As space science develops, man has learned more and more about space. Space is not only amazing but also dangerous. While working in space, spacemen are facing danger.
Scientists have found out that radiation(辐射） is the greatest danger to spacemen in space. When spacemen are working in space, they are in danger of radiation from the sun and other stars, which is bad for their health. The damage done by radiation won't be discovered until their children or even grandchildren are born. Some special medicine may work a little, but no really helpful medicine has been.
Space junk is also thought a great danger to spacemen. It's reported that there are 9,000 man-made things flying in space. About 30% of these are man-made satellites(卫星）, 10% are spaceships, and the rest are space junk. An explosion(爆炸） in 1996 made a cloud of 300,000 fragments, each at least 4mm in size, and even a small piece of these knocked against a spaceship window and did some damage. Scientists are watching and reporting any possible danger all the time. They are working on helpful ways to do with space junk.
Although space is really dangerous, it interests everyone on the earth. In the near future, it may become usual for people to spend a few days in a space hotel. We may even choose to leave the earth and live in space for a few years. So we should care for space and do something to help improve the space environment.
1. _________ shows the man-made things in space in the correct way.A． | B． |
C． | D． |
2. Space junk and radiation in space are dangerous to _______
| A．spacemen working in space | B．people only on the earth |
| C．all the people except children | D．the old people on the earth |
| A．烟霎 | B．泡沫 | C．云块 | D．碎片 |
| A．The passage tells us that radiation in space comes from the sun and other stars. |
| B．Every one of us can make a trip to space now. |
| C．Scientists have found out ways to solve any problem in space. |
| D．People are afraid to travel to space because it's too dangerous. |
| A．Space Radiation | B．Space Danger | C．Space Junk | D．Space Travel |
【推荐1】Do you know extreme（极限的）sports？Extreme sports are often dangerous．But many people like them．A lot of people want to do them，even women．Do you know why？One said，“Because they can make me so exciting．”Do you think so？Read about them below．Then you can know a lot about them．
| Bungee Jumping：People on some South Pacific（太平洋）islands have been bungee jumping for hundreds of years．In 1979，some people bungee jumped off a bridge in England and made the sport popular around the world．Bungee jumping came to China in 1996． |
| Skateboarding：At first，this sport was called“sidewalk surfing”．Skateboarder often jump high into the air，go down steps or slide（滑动）down rails on their boards．They wear baggy trousers so they can move more freely． |
| Skydiving：This is probably the scariest extreme sport．Skydivers jump out of airplanes about four kilometers up in the sky．They usually fall freely for a while and then open a parachute（降落伞）to slow down for a safe landing． |
| Snowboarding：This became a winter Olympic sport in 1998．People tied their feet to the board with special shoes．They don’t use any ski sticks．Then，they ride down hills，jump high and do tricks． |
1. What made bungee jumping popular all over the world？
| A．A history of hundreds of years． | B．Coming to China in 1996． |
| C．Jumping over a river in England． | D．Jumping off a bridge in Britain． |
| A．Bungee jumping and skydiving． | B．Skydiving and skateboarding． |
| C．Bungee jumping and skateboarding． | D．Snowboarding and skateboarding． |
| A．Bungee jumping． | B．Skydiving． | C．Skateboarding． | D．Snowboarding． |
【推荐2】It’s hard when a best friend isn’t around — maybe because you move to a different school or a different class. You may feel lonely at break (课间) or lunchtime. You want to have new friends, but how do you make them?
Start by looking around your classroom. Think about which kids you’d like to play with at break. Say hi to them, smile, and be friendly. Ask them to enjoy something or talk with them about something they may be interested in. Invite someone to play with you or ask “Do you want to sit here?” in the lunchroom. When you’re at break, walk to kids you want to play with, and say “Hi, can I play, too?” or just join in.
If you are feeling shy (害羞), ask your teacher to help you make new friends. Teachers are usually good at matching up friends. The best way to make friends is to be a friend. Be kind, be friendly, say nice things and help others —soon you’ll have one, or two, or even more new friends.
1. It’s when a best friend isn’t around.| A．difficult | B．easy | C．interesting | D．quiet |
| A．they miss their old friends a lot |
| B．they have no time to stay with Others |
| C．teachers are good at making friends |
| D．they are shy or not good at making friends |
| A．Teaching. | B．Working. | C．Making friends. | D．Learning. |
【推荐3】My neighbor, Mr. Black, is seventy years old. He always complains about how fast things have changed, and he often says that life used to be better than today.
Now cities are full of cars. Some families even have two or more cars, so parking is becoming a big problem. The traffic in some cities is very bad. Some car drivers drive so fast that there are more traffic accidents. Yesterday Mr. Black’s old friend died because a car hit him. He is very sad now.
Most families have computers now. Now more and more children use the Internet . The number of children using the Internet is becoming bigger and bigger. Mr. Black’s grandson is a high school student. He often plays computer games on the Internet till midnight. He falls asleep in the early hours of the morning and spends little time doing homework. His English teacher told Mr. Black that his grandson failed another test. Mr. Black got very angry with him.
And people talk less to each other than before. They are too busy to talk, too busy to eat, too busy to think.
Mr. Black thinks that life used to simple and happy, but now it has changed a lot.
1. Mr. Black thinks that the life now is_________.| A．more comfortable | B．worse than it used to be |
| C．better than it used to be | D．the same as it used to be |
| A．考虑 | B．期盼 | C．抱怨 | D．猜测 |
| A．Few people are using the Internet now. |
| B．People have more time to talk with each other now. |
| C．It is a problem to park cars in some cities. |
| D．The traffic is very bad in all the cities. |
| A．Mr. Black’s grandson is not interested in the Internet. |
| B．Mr. Black is worried about his grandson. |
| C．Mr. Black is an English teacher. |
| D．Mr. Black likes today’s life more than that of the old days. |
Eskimos live near the North Pole (北极). There are only two seasons there, winter and summer. There is no spring or autumn there. The winter nights are long. You can't see the sun for more than two months, even at midday. The summer days are long. For more than two months, the sun never goes down and there's no night.
Eskimos have warm clothes. They make their clothes from the skins of animals. From skins (皮毛) they make coats, caps and shoes. Near the North Pole trees can't grow, for it is too cold there. The Eskimos have to make their houses from skins, snow or stone. When they got out in storms and can't get back home, they make houses of snow. They leave these houses when the storm（风暴） is over.
Life is hard for the Eskimos, but they still like to live there.
1. Near the North Pole there are _____ in a year.
| A．two seasons - winter and summer |
| B．two seasons - spring and autumn |
| C．four seasons – spring，summer，autumn and winter |
| D．two seasons sometimes and four seasons sometimes |
| A．24 hours | B．Over a week |
| C．A month | D．Over two months |
| A．stones | B．animals | C．trees | D．clothes |
| A．days | B．nights | C．trees | D．animals |
| A．animals | B．stones | C．snow | D．rain |
【推荐2】Are you interested in Chinese traditional arts? Do you want to learn how to make them by hand? If so, come and join our clubs this weekend in our school.
 Sky Lantern Club Introduction: Sky Lanterns are made of bamboo and covered with paper. They were first used to ask for help when people were in trouble.They are used to show happiness and good wishes. Time:Saturday 8: 30 a m-10: 30 a m Place: Building 3 Room 501 |
 Paper Cutting Club Introduction: Paper Cutting turns a simple thing like a piece of paper into a beautiful piece of art. Pictures about flowers, animals and so on are put on win⁃ dows, doors and walls as symbols of good wishes and good luck. Time: Saturday 9: 00 a m-11: 00 a m Place: Building 3 Room 502 |
 Chinese Knot Club Introduction: Chinese Knots are usually made of red and yellow ropes. They are used to express good wishes, including happiness, love, peace and so on. Time: Sunday 2: 30 p m-4: 30 p. m Place: Building 3 Room 603 |
1. Sky Lantern are made of________?
| A．clay and paper. | B．bamboo and paper. | C．red ropes. | D．yellow ropes |
| A．Building 3 Room 603 | B．Building 3 Room 501 |
| C．Building 3 Room 502 | D．Building 3 Room 601 |
| A．Sky Lantern Club. | B．Paper Cutting Club. |
| C．Chinese Knot Club | D．All of them. |
| A．a notice . | B．a story. | C．a book. | D．a joke. |
| A．They are all made by machine. | B．They are all used ask for help. |
| C．They are all symbol of good wishes. | D．They are all put on windows. |
It’s good to make mistakes．And here’s why．
First of a11．mistakes are a clear sign that you are trying new things．It’s always good to try new things because when you’re trying new things you are growing．If you never try anything new,how can you improve and develop?The simple answer is,“You can’t.”
Another good thing about mistakes is this：When you are making mistakes，you are learning．Consider this：Edison failed 1 0,000 times— before he perfected the light bulb．When he was asked how it felt to fail that many times，he replied that he hadn’t failed 1 0,000 times，but rather had learned 10,000 things that didn’t work．
Finally,when you make a mistake，you are much closer to success．Why?Because every time you make a mistake，you are one step closer to success．But it doesn’t mean that you can make mistakes without thinking．Instead，when you try something new,you have to think it over，so that you can keep away from some unnecessary mistakes．
There is an old saying that goes．“If you are not making mistakes．you are not trying hard enough.’’ So go forward and make mistakes．And learn．And grow．And succeed．
1. According to the passage，when you are making a mistake，that means ．
| A．you’re thinking | B．you’re growing |
| C．you’re falling behind | D．you’re wasting time |
| A．move forward | B．never fail |
| C．learn nothing | D．make no mistakes |
| A．we are learning when we make mistakes |
| B．we should spend lots of time making mistakes |
| C．when we try new thjngs,we should think them over |
| D．the more mistakes we make，the further we are from success |
| A．not to make mistakes often |
| B．how to become successful quickly |
| C．it’s good to make mistakes |
| D．how to stay away from mistakes |
Laura is good at music. She wants to be an artist. She is going to sing and dance for people. Lisa wants to be a reporter. She says, “I am going to talk with many famous people and I can learn a lot from them.” “What do you want to be?” Lisa asks Tina. Tina says, “Oh, I want to be an
1. How many students are talking about their future work?
| A．Two. | B．Three. | C．Four. | D．Five. |
| A．Toby. | B．Laura. | C．Tina. | D．David |
| A．A doctor. | B．An engineer. | C．An artist. | D．A teacher. |
| A．助理 | B．经理 | C．口译工作者 | D．导游 |
| A．Why should we study hard? |
| B．How to study well? |
| C．What are they going to do? |
| D．How to be a famous person? |
【推荐2】Mouth is an important part of our body. When we eat food, talk with others, sing and smile, we use our mouth. Also, when learning English, we can find the word “mouth” in many sentences.
In everyday life, if someone says something bad about us, we can say “Do not bad mouth me” to talk back. Sometimes, if we say bad things that make others feel sad. we can say, “Sorry, I really put my foot in my mouth this time.” We can also use “I am down in the mouth” to tell others our unhappiness. Sometimes when we talk with a friend and we have the same ideas with him, we can say, “You take the words right out of my mouth!” If some people have lots of money because of their rich families, in English, we can say, “They were born with a silver spoon in mouth.” But a person who lives “from hand to mouth” is very poor and only has money to buy some cheapest things in need.
From the above examples, we can see that even the same English word can be used in different situations (情形)to tell others different feelings. English is a great language, isn’t it?
1. The writer tells us that we can find the word “_________”, an important part of our body, in many sentences.| A．nose | B．face | C．head | D．mouth |
| A．happy | B．relaxed | C．sad | D．boring |
| A．Do not bad mouth me | B．I’m from hand to mouth |
| C．I really put my foot in my mouth | D．You take the words right out of my mouth |
| A．five | B．six | C．seven | D．eight |
| A．English is a useful language. |
| B．We can use mouth to do many things. |
| C．Mouth is an important part of our body. |
| D．How people use the word “mouth” in different situations. |
A well-known speaker started his talking by holding up a $20 bill．In the room of 200, he asked, "Who would like this $20 bill?"
Hands started going up．He said, "I am going to give this $20 to one of you, but first, let me do this." He began to crumple(弄皱) the 20 dollar note up．He then asked, "Who still wants it?" Still the hands were up in the air．
"Well," he replied, "what if I do this?" He dropped it on the ground and started to grind it into the floor with his shoe．He picked it up, now crumpled and dirty．
"Now, who still wants it?" Still the hands went into the air．
"My friends, you have all learned a very valuable lesson．No matter what I did to the money, you still wanted it because it did not decrease in value．It was still worth $20."
"Many times in our lives, we are dropped, crumpled, and ground into the dirt by the decisions we make and the circumstances that come our way．We feel as though we are worthless; but no matter what happened or what will happen, you will never lose your value." "Dirty or clean, crumpled or finely creased, you are still priceless to those who love you．The worth of our lives comes, not in what we do or who we know, but by ...WHO WE ARE."
"You are special — don’t ever forget it."
1. This passage is mainly about ________．
| A．a famous professor |
| B．the value of $20 |
| C．the value of a person |
| D．the importance of money |
| A．the value of the money never changed |
| B．he was not interested in the money |
| C．he was a very special person |
| D．the money was valuable any more |
| A．become more |
| B．become less |
| C．change fast |
| D．stay the same |
| A．we should try our best to make more money |
| B．we should try to make ourselves special |
| C．we can word hard to prove ourselves |
| D．we might meet with a lot of difficulties in our life |
