How the Grand Canyon was created remains one of the geology’s greatest mysteries. Some geologists believed that the process was a gradual one: the Colorado River which goes through the canyon slowly cut deeper and deeper into the ground over millions of years. But some rocks of the volcanoes, which have been discovered in the canyon recently, suggest that the canyon was down-cut instead.
Down-cutting is when a flood of water rushes over a place with enough force to cut deeply into the ground and leaves behind a canyon. Such a flood is usually released when a natural or man-made dam breaks.
Robert Webb, a research geologist, says natural dams seem to have formed and broken across the Colorado River several times during the last million years. The dams were built when lava from the nearby volcanoes flowed into the river. The lava hardened into hard rocks and blocked the river, causing it to back up and form a lake. Each time the lake grew so huge that it broke the rock dam, releasing a flash flood that furthered the down-cutting process and deepened the canyon.
Down-cutting is not only an earthly event. Satellite photos sent back from Mars suggest that the process has happened there, too, say many other scientists. The photos, taken by the Mars Global Surveyor, indicate that an enormous lake existed on Mars 3.5 billion years ago. The lake spilled into a large nearby hole. One edge of the hole broke, releasing a flash flood that quickly carved out a huge canyon. The finding of down-cutting on Mars is just one more piece of evidence that the formation of the Grand Canyon was not a gradual course.
1. In the past, the Grand Canyon was believed to be made by ________.| A．a river running slowly over years | B．a volcano breaking suddenly |
| C．the rock rising from the earth | D．the ground moving gradually |
A． | B． | C． | D． |
| A．introduce a topic | B．give an example | C．show new ideas | D．compare with others. |
| A．The Grand Canyon—A Wonder With Huge Lakes | B．The Grand Canyon—A Wonder With Breaking Dams |
| C．The Grand Canyon—Results of River Going | D．The Grand Canyon—Results of Flood Cutting |
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【推荐1】Surtsey was born in 1963.Scientists saw the birth of this island. It began at 7.30 a.m. on 14th November. A fishing boat was near Iceland. The boat moved under the captain's（船长）feet. He noticed a strange smell. He saw some black smoke. A volcano（火山）was breaking out. Red-hot rocks, fire and smoke were rushing up from the bottom（底部）of the sea. The island grew quickly. It was 10 meters high the next day and 60 meters high on 18th November. Scientists flew there to watch. It was exciting. Smoke and fire were still rushing up. Pieces of red-hot rock were flying into the air and falling into the sea. The sea was boiling and there was a strange light in the sky. Surtsey grew and grew. Then it stopped in June 1967.It was 175 meters high and 2 kilometers long. And life was already coming to Surtsey. Plants grew. Birds came. Some scientists built a house. They want to learn about this young island. A new island is like a new world.
1. Surtsey is ______.| A．an island not far from Iceland | B．a new volcano | C．a fishing boat | D．a place in Iceland |
| A．to watch the birth of the island | B．to save the fishing boat |
| C．to learn about the island | D．to build a house |
| A．Before the volcano broke out. | B．As soon as the volcano broke out. |
| C．About four days after the volcano broke out. | D．After the volcano stopped rushing up. |
a. The captain found the boat was moving.
b. A new island appeared in the sea.
c. Fire, smoke and rocks were seen rushing up.
d. A fishing boat was near Iceland.
e. The island grew quickly.
| A．d-a-c-b-e | B．a-b-c-d-e | C．a-b-e-c-d | D．b-e-d-a-c |
| A．A new island | B．The birth of an island | C．A new world | D．Scientists discovered Surtsey |
【推荐2】Rainforests are home to a rich variety of medicinal plants, food, birds and animals. Can you believe that a single bush in the Amazon may have more species of ants than the whole of Britain! About 480 varieties of trees may be found in just one hectare of rainforest.
Rainforests are the lungs of the planet-storing vast quantities of carbon dioxide and producing a significant amount of the world’s oxygen. Rainforests have their own perfect system for ensuring their own survival; the tall trees make a canopy (树冠层) of branches and leaves which protect themselves, smaller plants, and the forest animals from heavy rain, intense dry heat from the sun and strong winds.
Amazingly, the trees grow in such a way that their leaves and branches, although close together, never actually touch those of another tree. Scientists think this is the plants’ way to prevent the spread of any tree diseases and make life more difficult for leaf-eating insects like caterpillars. To survive in the forest, animals must climb, jump or fly across the gaps. The ground floor of the forest is not all tangled leaves and bushes, like in films, but is actually fairly clear. It is where dead leaves turn into food for the trees and other forest life.
They are not called rainforests for nothing! Rainforests can generate 75% of their own rain. At least 80 inches of rain a year is normal-and in some areas there may be as much as 430 inches of rain annually. This is real rain-your umbrella may protect you in a shower, but it won’t keep you dry if there is a full rainstorm. In just two hours, streams can rise ten to twenty feet. The humidity (湿气) of large rainforests contributes to the formation of rainclouds that may travel to other countries in need of rain.
1. What can we learn about rainforests from the first paragraph?| A．They produce oxygen. | B．They cover a vast area. |
| C．They are well managed. | D．They are rich in wildlife. |
| A．Heavy rains. | B．Big trees. | C．Small plants. | D．Forest animals. |
| A．For more sunlight. | B．For more growing space. |
| C．For self-protection. | D．For the detection of insects. |
| A．Life-Giving Rainforests | B．The Law of the Jungle |
| C．Animals in the Amazon | D．Weather in Rainforests |
【推荐3】How do you feel about nature? After spending hours indoors, do you feel better when you visit your local park? Most people think that nature is good for our bodies and brains. However, humans are spending more time inside and less time outside. In some countries such as the USA, only 10% of the teenagers spend time outside every day. Many doctors feel that this is a problem in the twenty-first century.
Some doctors find nature and health are interrelated. One example of this is the work of Dr. Matilda in Sweden (瑞典). The doctor gave people a maths test. During the test, their heart rates (率) were fast. After the test, one group of people were chosen to sit in a 3D-virtual-reality (虚拟现实) room for fifteen minutes with pictures and sounds of nature. Their heart rates were slower than the others’. Another good example of how nature is good for health comes from Canada. In Toronto, researchers studied 31, 000 people living in the city. In general, they found that healthier people lived near parks.
Because of studies like these, some countries and cities want nature to be part of people’s everyday life. In Dubai, for example, there are plans for a new shopping mall with a large garden so shoppers can relax outside with trees, plants and water. In Switzerland, “forest schools” are popular. Students study their subjects in the forests and do lots of exercise outside. And South Korea is another good example. It has new forests near its cities and around 13 million people visit these forests every year. So after building cities for so long, perhaps it’s now time to start rebuilding nature.
根据短文内容选择最佳答案
1. The underlined word “interrelated” in the passage means “________’’ in Chinese.
| A．相互联系的 | B．毫不相干的 | C．相互排斥的 |
| A．slower than | B．faster than | C．the same as |
①the USA a. Children study in the forests and do lots of activities outside.
②Dubai b. About 13 million people visit new forests near its cities every year.
③Switzerland c. A new shopping mall with a large garden will be built.
④South Korea d. 10% of the teenagers spend time outside every day.
| A．①-a ②-d ③-b ④-c | B．①-d ②-c ③-a ④-b | C．①-d ②-c ③-b ④-a |
| A．Doctors find that many people don’t like spending time outside, which is a big problem in the twentieth century. |
| B．Canadian researchers found that healthier people lived near cities. |
| C．Dr. Matilda is a doctor from Sweden. |
| A．HOW TO LIVE LONGER |
| B．COUNTRY LIFE - HEALTHIER AND EASIER |
| C．NATURE - PART OF PEOPLE’S DAILY LIFE |
①The 2022 Beijing Winter Olympic Games opened on February 4, which coincided with “Lichun,” the first of the 24 solar terms（节气）in the traditional Chinese lunar calendar, showing the start of spring. “Lichun” also became an important element at the opening ceremony.
②Lichun is called “Start of Spring” in English. It is the first solar term in the year. It also shows the change of the season and marks the end of winter and the beginning of spring. The date for Lichun usually comes on February 4 or February 5 in solar calendar. After Lichun, days become longer and nights become shorter, while weather is getting warmer. The following is some information about this solar term.
Stand the egg
③In China, it is said that the egg can be set up on the first day of the spring. It is believed that if someone can make the egg stand on the first day of spring, he will have good luck in the future. Try to stand eggs today on your own. If you succeed in the challenge, it means good luck is coming.
Hold a special ceremony（仪式）
④People in China began holding a special ceremony on the day of Start of Spring about 3,000 years ago. In ancient China, people mainly lived on farming, and the change of seasons greatly influenced farming. Spring is the season for planting. After Lichun farmers may start to work in the field. And vitality（活力）heads back to all lives. For city people, time has come for them to do outdoor activities and enjoy warm sunshine.
Eat special food—Chunjuan
⑤People try to eat something new to keep the spring. There has been a long history of eating chunjuan during Lichun. People will wrap some vegetables with chunjuan. Besides enjoying chunjuan with vegetables, farmers will also send chunjuan as presents to each other.
1. Which of the following Chinese poem is about Lichun?| A．泥牛鞭散六街尘，生菜挑来叶叶春 | B．桂轮开子夜，萤火照空时 |
| C．闻道新年入山里，蛰虫惊动春风起 | D．露从今夜白，月是故乡明 |
| A．to be healthy | B．to have good luck | C．just for fun | D．to succeed |
| A．Warm sunshine. | B．The change of seasons. | C．The planting skills. | D．The outdoor activities. |
A． | B． | C． | D． |
A． | B． | C． | D． |
【推荐2】What age does doukou nianhua refer to?
In one of his poems, Tang Dynasty poet Du Mu once compared girls around the age of 13 to cardamom (豆蔻) flowers in the bud (含苞待放). Since then, doukou nianhua has been used to describe teen girls of this age.
Ancient Chinese people liked to describe someone’s age using titles (称谓), rather than the exact number. For example, chuitiao, meaning “straight hair”, meant a hairstyle that was popular for very young children in ancient China. It was used for children from 3 to 8 years old.
Zongjiao, meaning “twisted horn”, was used to describe children from 9 to 14 years old. Back then, children would divide their hair into two halves and twist each half into a knot (结) on the top of their head, just like two horns.
Shufa, meaning to tie one’s hair up, was used for boys who had reached the age of 15. Boys would let down their “twisted horns” and tie up their hair in a bunch (一束) when they turned 15.
Ruoguan, or “junior cap”, was used for young men in their twenties. These men would go to a hat-wearing ceremony when they turned 20 to show that they had become adults.
The “year of independence” was when a man turned 30.
At the age of 40, one “will not become puzzled”.
When a man turned 50, he had reached the “year of understanding the mandate (命令) of heaven”, meaning to become aware of one’s fate and no longer make any useless efforts.
Finally, if you were lucky to live past one hundred years, really a long life, you would be titled qiyi (期颐).
1. At what age do children reach the stage described by chuitiao?| A．3 to 8 years old. | B．13 years old. | C．9 to 14 years old. | D．15 years old. |
| A．zongjiao. | B．shufa. | C．ruoguan | D．chuitiao |
| A．These titles are from poems. | B．These titles are for adults. |
| C．These titles are for children. | D．These titles stand for long life. |
| A．不惑。 | B．而立。 | C．知天命。 | D．期颐。 |
| A．Interesting ancient people. |
| B．People of different ages hope for different things. |
| C．Zongjiao, shufa, and ruoguan are titles for ancient people. |
| D．Different titles in ancient times. |
【推荐3】Researchers in the 1960s found bilingual（双语的）people scored higher on intelligence （智力）tests than monolinguals—people who speak only one language. The latest studies show that being bilingual does not necessarily make people cleverer, but it probably does make you better at certain skills.
Imagine driving down the highway. There are many things that could attract your attention and you really need to be able to watch all of them. Why would bilingualism make you any better at that?
The answer is that bilingual people are often better at controlling their attention—a function（功能）called the executive control system. It’s quite possibly the most important system we have because it’s where all of your decisions about what to attend to, what to ignore（忽视），what to process are made.
The best method to measure（测量）the executive control system is called the Stroop Test. Suppose you would have the word blue written in red but you have to say the colour red. But “blue” is so eye-catching, and you really want to say “blue”. You need to ignore it so that you can say the colour red. That’s the Stroop Test.
Bilingual people continually practice this function. They have to, because both languages are active in their brain at the same time. They need to ignore one to be able to speak in the other. This exercise might help in other ways, too. Researchers say bilingual children are more likely to have trends from different cultures. Bilingual adults are often four to five years later than others in developing Alzheimer’s disease.
1. What did the recent research find about bilingual people?| A．They can safely drive their cars. |
| B．They can well manage their attention. |
| C．They can have a better control of imagination. |
| D．They can easily pick out the colours they want. |
| A．Red. | B．Blue. | C．Test. | D．System. |
| A．Bilingualism may do harm to people’s health. |
| B．Bilingualism helps children make more foreign friends. |
| C．People must practice speaking two languages continually. |
| D．People use more active words from their mother languages. |
| A．How does the Stroop Test work? |
| B．What is executive control system? |
| C．Are monolingual people smarter? |
| D．Are bilingual people better at some skills? |
Weixin can make people quick to send voice message, video, pictures and text by phone. Because it is sent by network（网络）, distance is not a problem. Even if your friends are in foreign countries, you can use Weixin to
Weixin supports Wi-Fi and 3G network. It can enjoy group chat up to 20 people. Besides this, it can do much. Weixin can search people around you. It also supports to send videos. You can share the wonderful pictures with other people at any tim . It can share your messages to the world and make new friends. Weixin can keep your pictures and texts in your phone. It also helps you to get your messages from others. Weixin makes more people “talk” with each other in different places at different times.
The cost of Weixin is very low. It costs nothing to own Weixin if you have a phone. The low cost is one of the main reasons why Weixin becomes popular. Many people say that it’s much more convenient than QQ. Nowadays these users can’t live without them. They chat on QQ and Weixin and express their thoughts on Weibo.
根据短文内容，选择最佳答案。
1. . The use of Weixin began . .
| A．in February, 2011 | B．in January, 2011 | C．in March, 2013 |
| A．联系 | B．交易 | C．视频 |
| A．3 | B．5 | C．7 |
| A．only young people use Weixin to talk with their friends |
| B．Weixin can help people make new friends |
| C．the cost of Weixin is much more expensive than that of QQ |
| A．how to use Weixin to communicate with others |
| B．Weixin’s functions and its advantages |
| C．Weixin’s influences on most people’s lives |
【推荐2】What season is it in October? If you ask people from the UK, they will tell you it’s “autumn”. But if you go to the US, you will find that people use both “autumn” and “fall”, why does this season have two names in English?
According to Dictionary.com, both words have been around for a long time, but neither of them was the first to describe this season. During this season, crops would become ripe (成熟) and farmers would have a big harvest. So in Old English, this season was simply called “harvest”.
Then, in the 1600s, more people left their farms and moved to cities. With fewer people farming, the word “harvest” became less useful. English speakers needed a different name for the season. They knew leaves fell from trees during the season, so people started calling it “the fall of the leaf”, or “fall” for short.
But at the end of the 1600s, autumn, from the French word “autompne” and the Latin “autumnus”, came to England. It gradually replaced (替代) “fall” as the word for this season.
At the same time, British people were making their first trips to North America. They brought both the words “fall” and “autumn” with them. That’s why today’s Americans have two names for one season.
1. What was the season in October called in Old English?| A．Autumn. | B．Fall. | C．Harvest. | D．Autompne. |
| A．Because leaves fell from trees. | B．Because crops would be ripe. |
| C．Because more people farmed. | D．Because it was more useful. |
| A．Chinese and Japanese. | B．French and Latin. |
| C．English and Indian. | D．Old English. |
| A．Four Seasons in a Year | B．Americans’ Favourite Season |
| C．One Season with Two Names | D．Differences between the UK and the US |
| A．In a storybook. | B．In a diary. | C．In a travel guide. | D．In a newspaper. |
Do you drink water that’s been left sitting out overnight or even for another day? Have you noticed it tastes different?
Tap water(自来水) that has been left to sit out slowly begins to get an off taste. Many people think that this is because of microorganisms(微生物). But that’s not what makes old water taste not fresh. For that we can think of carbon dioxide(二氧化碳). After about 12 hours, tap water starts to go flat as carbon dioxide in the air starts to mix with the water in the glass, lowering its PH and giving it an off taste. But it's most likely not harmful to drink.
However, back to those microorganisms. If you use a dirty glass day after day, there will be more chances to get bacteria(细菌). The risk will increase if you share the glass with another mouth as well. But supposing you use a fresh glass every few days, you probably won't have a problem unless the glass has been touched by dirty fingers, and especially if those dirty fingers went unwashed after using the bathroom.
As for plastic water bottles that have been left out in the sun or in the car, step away from the bottles, warns Dr. Kellogg Schwab, director of the Johns Hopkins University Water Institute. “A chemical named biphenyl-A, or BPA, along with other things used to make plastic can leach(过滤) into your water if the bottle heats up or sits in the sun,” he explains. BPA, as you probably know, has been linked to everything from serious heart problems to cancer. Schwab also adds that plastic used for commercial bottled water isn’t supposed to be washed or refilled, so use only one time and recycle. Or don't buy them at all; use refillable water bottles instead.
1. Tap water begin to have an off taste because of______.| A．carbon dioxide | B．BPA | C．the glass | D．the microorganism |
| A．has few microorganisms | B．is still safe to drink |
| C．tastes better than before | D．is likely undrinkable |
| A．To share the glass with another person. | B．To hold the clean glass with dirty hands. |
| C．To keep your hands and glass clean. | D．To drink after using the bathroom. |
| A．Use them after they cool down. | B．Clean them and use them again. |
| C．Throw the bottles away. | D．Refill them with fresh water. |
A．It is safe for people to use.  | B．It is a kind of new material. |
| C．It is the main material to make plastic. | D．It can cause great harm to people. |
