Stephen Warren, study leader at the University of Washington, has been on the case of the green icebergs for more than 30 years. He first took samples from one of these green hunks of ice in 1988, near the Amery Ice Shelf, East Antarctic. Most glacial ice occurs in shades of white to brilliant blue. The bluer the ice, the older it is. Typically, compression (压缩)from accumulating layers of snow pushes air bubbles out of the ice, reducing the scattering of white light. The compressed ice absorbs most of the light except for blue, creating the blue color seen in the hearts of icebergs and glaciers.
The green ice was similarly bubble-free, and yet it looked green instead of blue. Warren and his team soon found that the green ice came not from glaciers, but from marine ice. That's the ice from the undersides of floating ice shelves.
At first, the team thought that organic material in the marine ice was causing the green color. But further research showed that the green marine ice didn't have a higher — than — usual amount of organic impurities. Now, a new study finds that a different sort of impurity may be the root cause of the green ice. Warren and his colleagues report that the marine ice at the bottom of the Amery Ice Shelf has 500 times more iron than the glacial ice above.
This iron comes from the rocks under the Antarctic Ice Sheet, which are turned into fine powder as glaciers move over them. The icebound iron oxidizes (氧化)as it contacts seawater. The resulting iron oxide particles take on a green color when light scatters through them. When icebergs break off the larger ice shelf, they carry this iron-rich ice with them. It's like taking a package to the post office. The iceberg can deliver this iron into the ocean far away, and then melt and deliver it to other living things that can use it as a nutrient.
1. What's special about the iceberg found by Warren?| A．The iceberg was old. |
| B．The iceberg absorbed blue light. |
| C．The iceberg's heart was pure white. |
| D．The iceberg was bubble-free and green. |
| A．Impurities of marine ice. |
| B．Reflection of green plants. |
| C．Iron dust from marine ice. |
| D．Compression from layers of snow. |
| A．Deliver the package. |
| B．Bring marine life nutrients. |
| C．Oxidize the seawater. |
| D．Break off the large ice shelf. |
| A．A Study About Antarctic |
| B．The Colors of Icebergs |
| C．The Movement of the Icebergs |
| D．The Mystery of the Green Icebergs |
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【推荐1】The Dead Sea might be the most famous saline body in the world, but it’s by no means the only one. Here, we uncover some other salt lakes around the world.
Dead Sea
The most famous of the lot, the Dead Sea—also known as the Salt Sea—is a natural place to start. It’s technically not a sea at all, but a land salt lake. Its waters are mainly drawn from the Jordan River, and the high salinity (盐度) means no life can survive here, so don’t expect any colorful fish. However, much amusement results from the sea’s buoyancy (浮力): Bring some reading material to the waters and lie back—nature will do the rest.
Lake Assal
Surrounded by black volcano rocks, Lake Assal takes the title of being the lowest point in Africa. Vast salt fields mark its edges; the lake has long been at the centre of the area’s salt trade, on which the region’s African locals still rely. Though the area might not be suitable to live in, the waters are rich in minerals and related to health benefits.
Great Salt Lake
The biggest salt lake in the western hemisphere, and the one that gave Salt Lake City its name, the Great Salt Lake finds its home in northern Utah. What makes the lake well-known is not only the lake’s blue and green waters and white-sand beaches, but also Great Salt Lake State Park and Antelope Island State Park, both offering super hiking and biking trails, and great long views.
Don Juan Pond
Don Juan Pond might not win any prizes for its beauty—at four inches deep, it’s little more than a pond, but it is worth visiting. Its salinity content of almost 40 percent makes it one of the saltiest bodies of water on Earth, meaning it doesn’t freeze even when Antarctic temperatures drop to -50℃. And with suggestions that water in a similar form could exist on Mars, there’s more than one reason for scientists to study this fascinating dry, cold environment.
1. What can visitors probably do in Lake Assal?| A．Read books. | B．Have a hike. |
| C．Enjoy small fishes. | D．Take a bath in the lake. |
| A．Its great parks. | B．Its scientific value. |
| C．Its highest salinity. | D．Its specific location. |
| A．Dead Sea. | B．Lake Assal. |
| C．Don Juan Pond. | D．Great Salt Lake. |
【推荐2】Sanjiangyuan National Park
Located on the Qinghai-Tibet Plateau , the Sanjiangyuan covers about 123,100 square kilometeris .It is home to the headwaters of the Yangtze, Yellow and Lancang rivers, which help to nurture billions of lives. Hence it is also called China's water tower.
The giant panda national park
The giant panda national park covers about 27,000 square kilometers in three provinces – Sichuan, Gansu and Shaanxi in the country's west. The park is home to 1,631 wild pandas, accounting for 87.50 percent of the country's total wild panda population.
Northeast China tiger and leopard national park
Northeast China tiger and leopard national park is located in the northeast of Jilin and Heilongjiang provinces at the junction, with a total area of 1.4612 square kilometers. The park is China's most important settlement and breeding area of the Siberian tiger and Amur leopard. It is also an important wildlife distribution area and one of the areas with the richest biodiversity in the temperate zone of the Northern Hemisphere.
Hainan Tropical Rainforest National Park
Located in the south-central part of Hainan Island, Hainan Tropical Rainforest National Park covers an area of 4,269 square kilometers, covering more than 95 percent of the island's primary forest and 55 percent of its natural forest.
The park has the most concentrated distribution of the best preserved and the largest contiguous area of island tropical rain forest in China, an important part of the world's tropical rain forest, with a national representative and global protection significance.
1. Which park is called China's water tower?| A．The giant panda national park |
| B．Northeast China tiger and leopard national park |
| C．Hainan Tropical Rainforest National Park |
| D．Sanjiangyuan National Park |
| A．The giant panda national park | B．Northeast China tiger and leopard national park |
| C．Hainan Tropical Rainforest National Park | D．Sanjiangyuan National Park |
| A．Heilongjiang | B．Sichuan | C．Gansu | D．Shaanxi |
| A．The giant panda national park | B．Northeast China tiger and leopard national park |
| C．Hainan Tropical Rainforest National Park | D．Sanjiangyuan National Park |
【推荐3】Wonder of the Natural World
When I arrived, it was early morning and it was raining. I looked to the east—the sky was becoming grey. I got out of the car, went through a gate and walked along a dark path. There was nothing to see, but I knew it was there.
After about a mile, a stranger appeared beside the path. “Am I going the right way?” I asked. He knew where I was going. “Yes,” he replied. “you’ll get there in five minutes.” Finally, I came to some rocks and stopped. I looked over them, but it was silent and there was no sign of it.
Suddenly, the rain stopped and the clouds cleared. The sun rose behind me and shone on the rocks. Far below me, the ground fell away and down to a river. I was looking across one of the wonders of the natural world –the Grand Canyon.
I looked down to the Colorado River, a silver stream nearly one mile below me. If you put the two tallest buildings in the world on top of each other at the bottom of the canyon, they still would not reach the top. Then I looked across to the other side of the canyon. It was about fifteen miles away, maybe more. Finally, I looked to my left and to my right, and on both sides the canyon went far away for more than 200 miles. The Grand Canyon was not just big. It was huge!
I remained by the canyon for about half an hour, and I asked myself, “Is the Grand Canyon the greatest wonder of the natural world?” I certainly know the answer. What do you think?
1. Where does the passage most probably come from?| A．A magazine | B．A grammar book | C．A dictionary | D．A storybook |
| A．Because there was nothing | B．Because it was too dark |
| C．Because it was raining | D．Because it was in the morning |
| A．South | B．North | C．East | D．West |
| A．To give facts about the natural world. |
| B．To say how he feels about the natural world. |
| C．To tell an interesting story about the Grand Canyon. |
| D．To tell us an article. |
【推荐1】Unlike so-called basic emotions such as sadness, fear and anger, guilt emerges a little later, in line with a child's growing grasp of social and moral standards. Children aren't born knowing how to say “I'm sorry”; rather, they learn over time that such statements appease parents and friends—and their own consciences. This is why researchers generally regard so-called moral guilt, in the right amount, to be a good thing.
In the popular imagination, of course, guilt still gets a bad reputation. It is deeply uncomfortable—it's the emotional equivalent of wearing a jacket stuffed with stones. Yet this understanding is outdated. “There has been a kind of revival or a rethinking about what role guilt can serve”, says Amrisha Vaish, a psychology researcher at the University of Virginia, adding that this revival is part of a larger recognition that emotions aren't binary-feelings that may be advantageous in one context may be harmful in another. Jealousy and anger, for example, may have evolved to alert us to important inequalities. Too much happiness can be destructive.
And guilt, by prompting us to think more deeply about our own goodness, can encourage humans to make up for errors and fix relationships. Guilt, in other words, can help hold a cooperative species together. It is a kind of social glue.
Viewed in this light, guilt is an opportunity. Work by Tina Malti, a psychology professor at the University of Toronto, suggests that guilt may compensate for an emotional deficiency. In a number of studies, Malti and others have shown that guilt and sympathy may represent different pathways to cooperation and sharing. Some kids who are low in sympathy may make up for that shortfall by experiencing more guilt, which can control their disgusting behaviors. And vice versa: high sympathy can substitute for low guilt.
In a 2014 study, for example, Malti looked at 244 children. Using caregiver assessments and the children's self-observations, she rated each child's overall sympathy level and his or her tendency to feel negative emotions after moral wrongdoings. Then the kids were handed chocolate coins, and given a chance to share them with an anonymous child. For the low-sympathy kids, how much they shared appeared to turn on how likely they were to feel guilty. The ones more likely to feel guilty tended to share more, even though they hadn't magically become more sympathetic to the other children.
“That's good news,” Malti says. “We can be prosocial because we caused harm and we feel regret.”
1. The underlined word “appease” in the first paragraph is closest in meaning to “_________”.| A．content | B．disappoint | C．amuse | D．distract |
| A．general impression of guilt being overestimated |
| B．incorrect idea about the nature and function of guilt |
| C．out-of date belief of guilt being their primary burden |
| D．long-held prejudice against those who often feel guilty |
| A．It's necessary to ensure kids feel guilty about their wrongdoings. |
| B．Regretful kids need to be given a chance to correct their behaviors. |
| C．Feeling guilty has the power to make kids become more sympathetic |
| D．The highest guilt could possibly be found in kids with the lowest sympathy. |
| A．Guilt vs Sympathy | B．Good News for Guilty People |
| C．Don't feel Guilty About Your Guilt | D．What Lies Underneath Your Guilt |
【推荐2】In English it’s common to say, “I know this town like the back of my hand!” While we may know our towns really well, how well do we actually know our hands? Maybe not quite as well as we think, said a scientific study.
Matthew Longo and his team from University College London studied the left hands of 100 people. With their hands placed palms (手掌) down under a board, Longo’s team gave the instruction to point to their knuckles (指关节) and fingertips with a marker. How did they do? Not that well.
“People think their hand is wider than it actually is,” said Longo. He said they also seemed to think their fingers were shorter than their true lengths. People were most accurate when finding their thumbs, but became less accurate with each finger, up to their pinkies.
“It is connected to our sense of position,” explained Longo. Humans know where different parts of our bodies are, even if we can’t see them. “It tells us whether a joint (关节) is straight or not,” said Longo. “We also need to know the distances between our joints,” he went on. Our brains know the sizes and shapes of our bodies from the maps they make for themselves. “This experiment tried to find those maps,” he said.
Maybe maps don’t need to be perfect. But why aren’t our brains more accurate? Longo said our brains “see” areas based on our sense of touch, with the stronger the sense of touch in a specific body part, the bigger that body part seems. An example is our lips. As they have more nerves than our noses, our brain’s map shows our lips are bigger. The same thing can happen with body parts that have a lot of nerves. If you’ve ever had something stuck in your teeth, it probably felt huge! That’s because our tongues also have lots of nerves.
If you want to have some fun, try this test with your classmates. Get some boards and some markers and have them mark the spots where they think their knuckles and fingertips are. Compare their hands to the marker spots and see how well they have performed.
1. The underlined sentence “I know this town like the back of my hand!” in Paragraph 1 is used to _____.| A．tell the readers how well the author knows his town |
| B．introduce the topic of the passage |
| C．make the readers know more about their hands |
| D．show the readers a map of one’s body |
| A．People know their hands much better than the researchers think. |
| B．One’s lips are much bigger than one’s nose. |
| C．Our sense of touch helps us to know about our body parts. |
| D．The experiment by Matthew Longo proved useless. |
| A．a part of one’s hand | B．the name of one of the researchers |
| C．a tool for the experiment | D．a way to finish the research |
| A．How to know about our hands |
| B．Our Brain’s Magic “Map” |
| C．A Study by Matthew Longo |
| D．Our Hands and Our Town |
【推荐3】In recent years, stressed-out urbanites have been seeking refuge in green spaces for the proven positive impacts on physical and mental health, but the benefits of “blue space” — the sea and coastline, but also rivers, lakes, canals, waterfalls, even fountains — are less well publicized, yet the science has been consistent for at least a decade: being by water is good for body and mind.
“Many of the processes are exactly the same as with green space — with some added benefits, ” says Dr Mathew White, a senior lecturer at the University of Exeter.White says there are three established pathways by which the presence of water is positively related to health and happiness. First, there are the beneficial environmental factors, such as less polluted air and more sunlight. Second, people who live by water tend to be more physically active. Third — and this is where blue space seems to have an edge over other natural environments — water has a psychologically restorative effect. When you are sailing, surfing or swimming, says White, “you’re really in tune with natural forces there.” By being forced to concentrate on the qualities of the environment, we access a cognitive state honed over millennia. Water is, quite literally, immersive.
Catherine Kelly is a wellness practitioner who teaches classes in “mindfulness by the sea”. She says the sea has a meditative quality.
“To go to the sea is synonymous with letting go, ” says Kelly. “It could be lying on a beach or somebody handing you a cocktail. For somebody else, it could be a wild, empty coast. But there is this really human sense of: ‘Oh, look, there’s the sea’ — and the shoulders drop.”
1. Why do people go to the “blue space” for a relaxation ?| A．To seek positive effect on body and mind. |
| B．To have a good swim in the blue sea. |
| C．To consider the beneficial environmental factors. |
| D．To tend to be more careful and active. |
| A．The characteristics of the beneficial and friendly environmental factors. |
| B．The classification of being by water is good for body and mind. |
| C．The importance of the beneficial and friendly environmental factors. |
| D．The causes of being by water are good for body and mind. |
| A．Being interested. | B．Being forced. |
| C．Being involved. | D．Being moved. |
| A．Trick of the lesson | B．Secret of the happiness. |
| C．Sense of human beings | D．Broadness of the sea |
【推荐1】Official figures show that 101 people were killed in road accidents on the streets of London last year. The city wants to reduce the number of deaths and serious injuries on the capital’s roads to zero. It seems impossible. But it focuses more minds on an important question: What can help reduce accidents in a big city? Transport for London (TfL), the capital’s road and rail authority, has some answers: safe speeds, safe vehicles and so on.
A safety standard for Heavy Goods Vehicles (HGVs), which harnesses blind area cameras and sensors (传感器), is pioneering. Blind area cameras and sensors are widely placed where they are needed. The European Commission has followed it. TfL has also helpfully identified London’s most dangerous places. Half of Britain’s most dangerous roads run through the capital. Around three-quarters of accidents that cause deaths or serious injuries happen at crossing near the British Museum, which has been the site of the most deaths since 2012. Westminster is the most dangerous area for walkers and cyclists, so it introduced 20 mph speed limits on all its roads in 2021.
“Vision Zero” was launched in 2018. Deaths and serious injuries on London’s roads have fallen — by 53% and 40% respectively in 2022. But movement is not one-way. Deaths were record breakingly low in 2020 and 2021. But in 2022 the deaths rose again. “We are moving in the right direction,” says Will Norman, London’s walking and cycling commissioner.
Lack of funds for TfL has put off improving the riskiest areas. Only a few parts of the1010 Avenue have bike paths with guardrails (护栏). Safety is the biggest problem to people taking up cycling or letting their children walk or cycle. But greener vehicles may be unsafe themselves. Electric scooters (滑板车) are the latest ones to confuse planners. “One of those doing 50 mph down the road is not good for anybody,” said Mr Norman.
1. What is the author’s purpose in writing paragraph 1?| A．To make the article interesting. |
| B．To stress the importance of TfL. |
| C．To call on scientists to study the question. |
| D．To give some background information. |
| A．Compares. | B．Removes. | C．Uses. | D．Replaces. |
| A．Doubtful. | B．Supportive. | C．Puzzled. | D．Unclear. |
| A．Bike lanes are not safe anymore for riders on roads. |
| B．Children should think twice when taking up cycling. |
| C．Safety has been a problem for some eco-friendly vehicles. |
| D．Electric scooters have become the biggest confusion for planners. |
【推荐2】More than 3,400 years after two ancient Egyptians were laid to rest, the jars of food left still smell sweet. A team of analytical chemists and archaeologists (考古学家) has analysed these smells to help identify the jars’ contents. The study shows how the exploration of smell can enrich our understanding of the past.
The 1906 discovery of the undisturbed tomb (墓穴) of Kha and Merit symbolized an important stage in Egyptology. The tomb remains the most complete non-royal ancient one ever found in Egypt, showing important information about how high-ranking individuals were treated after death.
Unusually for the time, the archaeologist who discovered the tomb resisted the temptation to open the sealed containers even after they were sent to the Egyptian Museum. The contents of many of these containers are still unknown, although there are some clues, says analytical chemist Ilaria Degano. “From taking with the museum keeper we knew there were some fruity smells in the display cases,” she says.
Degano and her colleagues placed various artefacts (人工制品) inside plastic bags for several days to collect some of the chemical substances they released. Then the team used a special machine to identify the components of the smells from each artefact. They found some chemicals associated with dried fish, and some chemicals common in fruits. The findings will feed into a larger project to reanalyse the tomb’s contents and produce a more comprehensive picture of burial customs for non-royals that existed when Kha and Merit died, about 70 years before Tutankhamun became the Egyptian ruler.
Aside from showing more about past civilizations, ancient smells could make museum visits more inviting. Usually, people admire exhibits with their eyes in museums. “Smell is a relatively unexplored gateway to the collective past for museum visitors,” says Cecilia Bembibre at University College London. “It has the potent alto allow us to experience the in a more emotional, personal way, through our nose.”
1. What can we describe the 1906 discovery of Kha and Merit’ tomb as?| A．A landmark in Egyptology. | B．A turning point in human history. |
| C．A breakthrough in archaeology. | D．A mirror of ancient non-royal life. |
| A．Pressure. | B．Ambition. | C．Desire. | D．Tendency. |
| A．protect them from harm | B．gather their smells |
| C．test the special machine | D．back up a larger project |
| A．They bring them back to the past. |
| B．They give them emotional support. |
| C．They change their view on civilizations. |
| D．They add to their experience. |
【推荐3】Canada has reintroduced some bisons (北美野牛) to the country’s oldest national park in Banff, Alberta, officials said on Monday, more than 130 years after the North American animal last appeared on the eastern slopes of the Canadian Rockies.
The protection team moved a group of 16 bisons into enclosed grassland in Banff National Park in the west of the province last week. The group will stay under observation in the Panther Valley until next summer, when the animals will be released into the full 1,189 sq km reintroduction zone in the park’s eastern valleys.
Parks Canada said bisons were once main grazers (plant-eaters) and that bringing them back would recover their missing role in Banffs ecosystem. “This would be one of only four bison groups in North America that would be fully interacting with their predators (meat-eaters) and shaping the ecosystem as they did over a hundred years ago,” said Karsten Heuer, the bison reintroduction project manager. Those predators will include wolves and bears native to the park.
Ten pregnant female bisons and six young bulls were disease-tested before being driven 400 km across Alberta by truck. Since the Panther Valley is not easy to reach by road, officials attached the containers by a long line to a plane and flew them in one at a time for the last 25 km.
Vast bison groups of up to 30 million animals once lived freely across North America. The animal was nearly hunted to extinction, and park keepers estimate bisons have not grazed in Banff National Park since before it was set up in 1885.
1. Why did the protection team move bisons into enclosed grassland?| A．To observe them. | B．To protect them. |
| C．To cure diseases. | D．To change their habits. |
| A．To reshape Banff’s ecosystem. |
| B．To help the bison population expand. |
| C．To make the oldest national park worth visiting |
| D．To recover their predators’ role in the ecosystem. |
| A．Deadly diseases. | B．Cruel hunting. |
| C．Natural predators. | D．Worsened ecology. |
| A．To show how to protect bisons. |
| B．To describe the living condition of bisons. |
| C．To explain how to transport bisons to Banff. |
| D．To inform readers of bisons returning to Banff. |
