Most of us have looked up at the stars that fill the night sky and wondered whether we’re alone in the universe. Indeed, the question of whether there’ s life out there has been something humankind ’s been asking itself for countless years. But thanks to China’s Five-hundred-meter Aperture Spherical Telescope (FAST), the answer to this question may come a lot sooner than we expected.
The telescope has a huge round reflector, which measures 500 meters across and has a perimeter（周长）of 1.6 kilometers. Because of its great size, it would have been both difficult and inefficient to get FAST to move like a regular telescope. Instead, FAST’s designers came up with a great solution: its surface is made up of 4450 panels which can be individually adjusted. This clever design feature allows scientists to detect radio signals from any angle with a great degree of accuracy. “Panels can change their positions through connected wires and parallel （关联的） robots. We can control their position with an accuracy of 1 mm,” Zheng Yuanpeng, chief engineer of the telescope’s panel project, told Xinhua News Agency.
FAST’s engineers also had the task of finding a suitable location. As any interference would affect its ability to detect distant radio waves, it needed to be built in a remote area. Luckily, the perfect spot was found in the beautiful mountains of Guizhou Province. “There are three hills about 500 meters away from one another, creating a valley that is perfect to support the telescope," Sun Caihong, chief engineer of FAST’ s construction, told Xinhua.
And although it wasn’t yet fully operated, FAST had already made great discoveries by October 2017. Since 1967, only around 2000 pulsars （脉冲星） have been discovered, yet FAST had detected six more by October 2017. Once FAST is fully up and running, we may finally have the answer to one of the biggest questions in history.
1. What is the purpose of mentioning the question in Paragraph 1?| A．To introduce the new giant telescope. |
| B．To explain why there is life in universe. |
| C．To remind readers to think about the life in space. |
| D．To emphasize the question that should be answered. |
| A．The telescope is made up of many panels. |
| B．The area of FAST is about 800 square kilometers. |
| C．The engineer can handle FAST’s position accurately. |
| D．The individual panel helps scientists catch radio signals. |
| A．Because Guizhou is a remote province. |
| B．Because Guizhou has an ideal valley. |
| C．Because Guizhou has beautiful mountains. |
| D．Because Guizhou has the ability to build it. |
| A．FAST’s timeline. | B．FAST’s future. |
| C．FAST’s operation. | D．FAST’s discoveries. |
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【推荐1】A scanning system combined with artificial intelligence is automatically assessing cows’ health status twice a day on dozens of “smart” dairy farms across the UK.
Overhead three-dimensional cameras film the animals’ backs as they leave the milking bam, while sensors read their individual identity tags. The associated computers then use machine learning to process the data, providing farmers with critical daily information about each cow’s weight, body condition and mobility. “We can detect certain health conditions, including lameness (跛行) , just by scanning the cows walking past, without even having to see their hooves (蹄子),” says Wenhao Zhang at the University of the West of England (UWE) in Bristol, UK.
While farmers are well trained to recognise such issues as early as possible, they often miss subtle, day-to-day changes in individual cows. Because they are a prey (猎物) species, cows will also naturally hide signs of discomfort, such as lameness, when they think they are being watched, says Melvyn Smith, who designed the system with Mark Hansen, both at UWE.
In an initial study of 200 dairy cows on one farm, Smith, Hansen and their colleagues placed a computer and 3D cameras in a milking bam. They aimed the cameras over an arrow walkway that cows pass through when they are finished milking. A near tag reader,set at the cows, head level, sets off the cameras to record. “The beauty of this equipment is that it’s just passively sitting there, unobserved by the animal,” says Smith. “And every time they go past — so every time they’re milked, which is usually twice a day — it’s gathering data.”
Kate Dutton-Regester at the University of Queensland in Australia says the system is “a great innovation”. “The dairy industry needs an automated, non-intrusive (非侵入式) monitoring system that can aid dairy farmers in observing the health of their herd in a timely and efficient manner, and this technology meets those criteria,” she says.
1. What can we know about the scanning system?| A．It was designed by Wenhao Zhang. |
| B．It can monitor the health of the cows. |
| C．It can help cure the lameness of the cows. |
| D．It provides farms with farming information. |
| A．To compare different scanning devices. |
| B．To demonstrate their high skills in farming. |
| C．To stress the advantage of the scanning system. |
| D．To introduce the operation of the scanning system. |
| A．It includes a 3D camera. | B．It can gather data. |
| C．It can’t be noticed by cows. | D．It is beautifully designed. |
| A．The dairy industry needs improving. |
| B．Well-trained farmers will be replaced. |
| C．The scanning system has been widely used. |
| D．The scanning system benefits the dairy industry. |
【推荐2】Researchers at CU Boulder have developed a wearable device that changes the human body into a biological battery. The device is stretchy(弹性的) enough that you can wear it like a ring, sport band or any other thing that touches your skin. It also taps into a person's natural heat-employing thermoelectric generators to change the body's internal temperature into electricity. "In the future, we want to be able to power your wearable electronics without having to include a battery," said Jianliang Xiao, an associate professor at CU Boulder.
The concept may sound like something out of The Matrix film series, in which a race of robots have enslaved humans to harvest their precious organic energy. Xiao and his colleagues aren't that ambitious: Their devices can generate about 1 volt (伏特) of energy for every square centimeter of skin space-less volt per area than what most existing batteries provide but still enough to power electronics like watches or fitness trackers.
Scientists have previously experimented with similar wearable devices, but Xiao's is stretchy, can heal itself when damaged and is fully recyclable-making it a cleaner alternative to traditional electronics. "Whenever you use a battery, you're depleting(消耗) that battery and will, eventually, need to replace it," Xiao said. "The nice thing about our device is that you can wear it, and it provides you with constant power."
Just pretend that you're out for a jog. As you exercise, your body heats up, and that heat will radiate out to the cool air around you. Xiao's device captures that flow of energy rather than let it go to waste. "The thermoelectric generators are in close contact with the human body, and they can use the heat that would normally be sent into the environment," Xiao said.
1. What does Xiao expect of his device at present?| A．It will be used for medical purposes. |
| B．It will be made smaller and wearable. |
| C．It will change natural power into electricity. |
| D．It will supply constant power to wearable devices. |
| A．To give an explanation. | B．To make a comparison. |
| C．To introduce a topic. | D．To analyze the cause. |
| A．The strengths of Xiao's device. |
| B．The convenience of using a battery. |
| C．The replacement of wearable devices. |
| D．The development of traditional electronics. |
| A．It operates with plenty of power. |
| B．It is designed for practical use. |
| C．It benefits people's health in a way. |
| D．It's based on traditional electronics. |
【推荐3】A rising star from Virginia has secured the title of “America’s Top Young Scientist” for his groundbreaking creation — a bar of soap designed to battle against skin cancer. At just 14 years old, Heman Bekele emerged as the victor of the 2023 Young Scientist Challenge, standing out among the ten finalists with his innovative creation known as the Skin Cancer Treating Soap (SCTS).
Bekele’s brilliant concept centers on the development of a soap that is not only affordable, but also has the potential to reactivate the body’s natural defenders of the skin to stop skin cancer. In Bekele’s own words, “Curing cancer, one bar of soap at a time. ”He always has endless passion for biology and technology, and the Young Scientist Challenge just provided him with the perfect platform to display his ideas. Reflecting on his inspiration, Bekele shared that his childhood played a significant role in shaping his innovative thinking. Having witnessed people work tirelessly under the sun, he couldn’t help but wonder how many were aware of the risks associated with constant sun exposure.
“I wanted to make my idea not only scientifically exceptional but also accessible to a broad audience,” Bekele expressed during an interview with the media. He received invaluable guidance from Deborah Isabelle, a product engineering specialist, who connected him with other scientists to aid him in reaching his ambitious plans.
During his presentation, Bekele passionately expressed his vision of turning the soap into “a symbol of hope, accessibility, and a world where skin cancer treatment is within reach for all.”
Over the coming five years, Bekele longs to perfect his invention and establish a nonprofit organization devoted to distributing his innovative creation to more places including undeveloped communities, offering hope and a practical solution in the fight against skin cancer.
1. What made Bekele an instant hit?| A．Starting a soap fashion. | B．Overcoming skin cancer. |
| C．Being the youngest scientist. | D．Creating a soap against skin cancer. |
| A．His concern for others. | B．His adventure in childhood. |
| C．His enthusiasm for technology. | D．His interest in medical knowledge. |
| A．Obtain official approval. | B．Visit undeveloped areas. |
| C．Increase the availability of the soap. | D．Update the facilities of production. |
| A．Inspiring and modest. | B．Humorous and positive. |
| C．Creative and considerate. | D．Curious and independent. |
Maybe your mum or dad has told you, "Turn that down before you go deaf!" Well, they are quite right. Loud noise might cause hearing loss for a short time or even forever. Think that earphones are a good way to escape from tour parents’ eyes? Well. It may not be as good a way as you expect. American doctors have studied a group of 44,000 people who used earphones more than 15 hours per week. The doctors found that 37,000 of them were getting hearing problems.
If you use earphones for too long a time, your ears might feel painful. You could also lose your hearing for the rest of your life. So don’t wear your earphones too long. Use them less than one hour a day. Want sharp hearing? Don’t forget to do the following: Try to stay away from places where there is too much noise, like a disco. If you have to go, wear earplugs. When swimming, remember to put earplugs into your ears to stop water from getting in. Never put anything sharp into your ears. If you think you have too much earwax, ask your mum or dad to help you clean it out.
Keep these things in mind! Then you won't be saying "WHAT???" when you are older.
1. Using earphones "may not be as good a way as you expect" because _______.
| A．your parents know what you're doing |
| B．it can cause hearing problems |
| C．it makes your parents angry |
| D．most of you use them improperly |
| A．have your ears specially trained |
| B．often wear earplugs and clean out the earwax |
| C．take good care of your ears |
| D．choose what you listen to carefully |
| A．has become impatient |
| B．speaks in a loud voice |
| C．is slow in understanding |
| D．asks for a lot of repetition |
【推荐2】Boredom is a common human experience. It’s almost impossible to fully avoid it, especially when you’re living a fast-paced life. You may be bored from time to time and feel like you need something new or exciting in your life. It’s perfectly natural to feel this way from time to time, but feeling bored often can also mean that your present life isn’t satisfying you as much as it could.
When you feel bored, think about what activities bring you joy and happiness. Perhaps you find that hobbies are what help improve your spirits when life feels standstill. After all, having interests and pursuing (追求) them often can have a great effect on the quality of your life and how satisfied you feel. If this sounds like something that would benefit your life, we have some great ideas for hobbies to pursue when you’re bored!
One of the easiest and most effective ways to relieve (缓解) boredom is to take exercise. Exercise is not only good for your body but also your mind. When your body is moving, it releases (释放) certain chemicals that make you feel good. Learning a new language is another way to challenge yourself and become more creative. It can also open up a whole new culture and way of thinking for you! Many people find that learning a new language gives them a sense of achievement that they don’t get from other hobbies.
Furthermore, reading is a hobby that can be enjoyed by almost anyone. It’s inexpensive, easy to fit into your plan and can be done just about anywhere. It doesn’t require special equipment or supplies, and you can do it alone or with others. The last way to avoid feeling bored inside is to spend time outdoors. Find a place to go where you can get away from the noise and other troubles. You may find that being outside offers a sense of peace and calmness.
Boredom is a common part of life, so we shouldn’t try to avoid it completely. Boredom can be a sign that you need a change in your daily life and something new to try. If you find yourself feeling bored, use these ideas to find new hobbies. After all, hobbies can greatly enrich your life and help you feel more satisfied!
1. When will we get bored according to the text?| A．When our present life doesn’t make us satisfied. |
| B．When we live a peaceful and happy life. |
| C．When we don’t have a fast-paced life. |
| D．When our life is exciting. |
| A．Most people feel satisfied with life all the time. |
| B．Reading a book requires special equipment and supplies. |
| C．Taking exercise is an effective way to keep off boredom. |
| D．All of us should try our best to avoid boredom completely. |
| A．Two. | B．Three. | C．Four. | D．Five. |
| A．Boredom is possible to avoid |
| B．Several activities can help relieve boredom |
| C．Learning a new language makes us more creative |
| D．Our body can release chemicals when we are moving |
【推荐3】From 1990 to 2000, fishermen trying to get swordfish (剑鱼) off the coast of California accidentally caught and killed over 100 sea turtles (海龟), and injured many more. In 2001, the government set up the Pacific Leatherback Conservation Area (PLCA), an area off the coast of California where fishing boats are not allowed to enter from August to November. Since then, the number of turtles killed by mistake has fallen rapidly, but a small number of animals still die from being caught in fishing nets each year. And at the same time, the once $15 million swordfish industry has become a $ 2 million industry.
Scientists are hoping to find a way to not only protect sea turtles and other endangered creatures but also help fishermen make a living. For this, many scientists are looking at dynamic ocean management to help fishing boats meet fish where they are and avoid catching other creatures by mistake.
The first paper to suggest that the fish living in the open ocean should be guarded with fluid, ever-changing zones of protection, came out in 2000. Larry Crowder, a professor at Hopkins Marine Station, remembers reading it and thinking, “Cool idea, but it will never work.” In 2000, scientists didn’t have the computer power to cheaply test statistical models or deal with satellite data quickly. They didn’t have enough data dealing with fish or satellite data on ocean conditions, either.
Now scientists can download satellite data of oceans in minutes and attach satellite archival tag to sea animals to track their movements. They first collect data by marking the creatures, collecting reports from fishing boats, or other tracking ways. Then they compare that data with weather conditions, the time of year, and any other data that can be sensed. Finally, they can predict where fish probably are.
Crowder and his workmates used the data to develop a tool called EcoCast during the 2012 and 2015 fishing seasons, they could have fished in at least 125,000 square miles, without high risk of hunting turtles.
1. The government hoped that PLCA and its rules could .| A．prevent fishing in the PLCA |
| B．help collect data for future research |
| C．protect the creatures in the area to some degree |
| D．make the public realize the importance of our environment |
| A．unrealistic | B．stupid | C．possible | D．interesting |
| A．A great way to collect data. |
| B．Some technology fruits in this field |
| C．A scientific way to find new ocean animals |
| D．The way dynamic ocean management works |
| A．It protects the ocean from pollution. |
| B．It helps support the fishing industry. |
| C．It prevents fishermen from getting lost while fishing. |
| D．It both protects ocean animals and supports the fishing industry. |
【推荐1】As winter sets in, it’s the perfect time to get out of town and escape the seasonal mood disorder. Here are vacation ideas to adopt now.
Costa Rica
Costa Rica, located in the Valle del General, is an off-the-radar agriculture town that’s not overrun with tourists. The area is known for its coffee, pineapples and sugar cane plantations, as well as its rich forests. What’s more, you can enjoy horseback riding, spend afternoons at the spa or tour a nearby wildlife shelter to look out for colorful birds, sloths and other animals.
Los Cabos, Mexico
If you love wine, travel to Los Cabos, a beautiful vacation destination at the southern edge of the Baja Peninsula. During your getaway(短假), you can enjoy special wine tastings and dinner cooked by Los Cabos’s Michelin-starred chef. There are wildlife-viewing opportunities, too. From December through May, you can spot whales, manta rays and more wildlife.
Petit St Vincent, the Grenadines
This private Caribbean island was free of the anger of hurricanes Irma and Maria. What’s more, the whole island is only 115 acres and has 22 cottages. Each cottage is located in a quiet place, and you can expect to unplug and recharge phones with no wireless connections, televisions or telephones in the cottages. Even better, you can spend your days admiring fascinating marine life at the Jean-Michel Cousteau Diving Caribbean center.
The Exumas, Bahamas
On Fowl Cay’s 50-acre private island, you can enjoy a carefree escape. Days can be spent fishing, boating and diving before wandering along white sands. The resort(度假村) features large one-, two- and three-bedroom houses. Best of all, if you’re planning a group getaway or multigenerational trip, you rent the entire island for a one-of-a-kind island escape.
1. Why does the author recommend these placed to readers?| A．To experience out-of-town sights. |
| B．To beat winter blues. |
| C．To escape from extreme weather. |
| D．To treat mental disease. |
| A．It survived hurricanes Irma and Maria. | B．It’s a huge and quiet island. |
| C．People can admire fish off shore. | D．People can charge phones using wireless connections. |
| A．Los Cabos, Mexico. |
| B．Petit St Vincent, the Grenadines. |
| C．Costa Rica. |
| D．The Exumas, Bahamas. |
【推荐2】2020 is special. When we dip into the model “suspended class, ongoing learning” during the pandemic(大流行）of NCP, have you thought of the inventors that supply us the convenience on the computers? Here, let’s know a respectable person who left us a few months ago.
Larry Tesler: computer scientist ,an icon of early computing, died at the age of 74 in this spring. Mr Tesler started working in Silicon Valley in the early 1960s, at a time when computers were inaccessible to the vast majority of people.It was thanks to his innovations ,which included the “cut”, “copy” and “paste” commands that the personal computer became simple to learn and use. Xerox, where Mr Tesler spent part of his career, paid tribute to him. “The inventor of cut/copy & paste, find & replace, and more, was former Xerox researcher Larry Tesler,” the company tweeted. “Your workday is easier thanks to his revolutionary ideas.”
Mr Tesler was born in the Bronx, New York, in 1945, and studied at Stanford University in California. After graduating, he specialised in user interface(界面) design, that is, making computer systems more user-friendly. He worked for a number of major tech firms during his long career. He started at Xerox Palo Alto Research Center (Parc), before Steve Jobs invited him for Apple, where he spent 17 years and rose to chief scientist. After leaving Apple he set up an education firm, and worked for brief periods at Amazon and Yahoo.
In 2012, he told the BBC of Silicon Valley: “There’s almost a custom -- after you’ve made some money, you don’t just retire, you spend your time funding other companies.”
“There’s a very strong element of excitement, of being able to share what you’ve learned with the next generation.” he added.
1. Which of the following is true according to the second paragraph?| A．Mr Tesler innovated the computer. |
| B．Mr Tesler invented the “cut”, “copy” and “paste” commands. |
| C．Mr Tesler spent part of his career as a data man in Xerox company. |
| D．Most people have many chances to use computers in the early 1960s. |
| A．three | B．four | C．five | D．six |
| A．selfless | B．friendly | C．special | D．humorous |
| A．Educating the next generation. |
| B．Discussing his retired life. |
| C．Showing the prospect of the Silicon Valley. |
| D．Sharing his knowledge with the next generation. |
【推荐3】It happened again last week.One of my relatives asked me, “My dear girl, you work in oncology(肿瘤科）？ Isn't that depressing?” I have heard those questions many times as an oncology nurse and my response is always the same.I tell them no,and that I love it.And then I smile.
I work in the Bone Marrow Transplant Unit at North Shore University Hospital.Together with my colleagues,we get to know most of our patients very well.We learn about their likes and dislikes.We get to meet their families and they take pictures of us.They tell us about a favorite vacation they once took and they wish us a good time when we are leaving for one.They also tell us to enjoy every moment of the day because we never know when life is going to change.
I am thinking of a recent experience we had with our patient Jim,a middle-aged man who is always expecting good things to happen and hopeful about the future.He was diagnosed with liver cancer a year ago and was facing the real possibility that he did not have a long time to live.But Jim voluntarily made up his mind to try for some very experimental treatments, even though the pain was almost too great to tolerate.
Eventually,Jim's disease went into remission.It is Easter Sunday now and he is home with his family.Jim got a miracle.An important reason why I work in oncology is that sometimes, not usually, not even very often, miracles do happen.And when they do,I am filled with gratitude and pride that as a nurse,I can be a part of that miraculous process.
Now you know why I smile when people ask me if I find oncology nursing to be sad or disappointing.I recall all the miracles I have seen and I remember what my patients have told me and I can't help but smile.
1. What is the author's impression of most about her patients?| A．They are overcome with depression. |
| B．They are keen to go sightseeing. |
| C．They stay positive despite illnesses. |
| D．They fail to understand her work. |
| A．She has a real talent for nursing. |
| B．The experience benefits her a lot. |
| C．Her job is respectable and well-paid. |
| D．Patients can get miracles under her care. |
| A．remained the same |
| B．began to improve |
| C．changed for the worse |
| D．reached a critical stage |
| A．One man's meat is another man's poison. |
| B．Health is not valued until sickness comes. |
| C．Where there is great love, there are always miracles. |
| D．An optimist sees an opportunity in every catastrophe. |
【推荐1】People often say that the Englishman’s home is his castle. They mean that the home is very important and personal to him. Most people in Britain live in houses rather than flats, and many people own their homes. This means that they can make them individual; they can paint them, and change them in any way they like. Most houses have a garden, even if it is a very small one, and the garden is usually loved. The house and the garden are the private space of the individual.
People usually like to mark their space. Are you sitting now in your home or on a train? Have you marked the space around yourself as your? If you are on the train you may put your coat or small bag on the seat beside you. If you share a flat you may have one corner or chair which is your own.
Once I was travelling on a train to London. I was in a section for four people and there was a table between us. The man on the space on my side of the table at all. I was angry. Maybe he thought that he owned the whole table. I had read a book about non-verbal communication so I took various papers out of my bag and put them on his briefcase! When I did this he stiffened and his eyes nearly popped(瞪出)out of his head. I had invaded his space! A few minutes later I took my papers off his case in order to read them. He immediately moved his case to his side of the table. Of course, it is possible that he just wanted to be helpful to me!
If you are visiting another country you may feel that you don’t have any private space. Hotel rooms look much the same in every country in the world. All day long, you share public spaces with other people. You see the local people in their private spaces and you feel lonely and “outside”. Local people can create their private spaces by talking about things you don’t know about .And you even feel that they like you to be outside them so that they will enjoy being inside even more! This is one of the difficulties of being a traveler! But if you understand it then it helps you. Haven’t you enjoyed being part of a group and “owning” a bit of space?
1. The writer was angry as he was travelling on a train to London because ________.| A．he had no place to sit |
| B．someone had invaded his “space” |
| C．too many people shared a section with him |
| D．some other people talked about things he didn’t know about |
| A．public spaces | B．private spaces |
| C．local people | D．other countries |
| A．British people dislike marking their space. |
| B．You always feel at home in another country. |
| C．Most British people prefer living in houses to flats. |
| D．You can’t mark your private space in a foreign country. |
| A．own private spaces by living in houses |
| B．have one corner of their own in public places |
| C．realize the importance of “space” in communication |
| D．create their private spaces by talking with local people |
【推荐2】Big, old trees are dying faster than in the past, leaving younger, less biodiverse forests that store less carbon worldwide. They give us paper and fuel, as well as vital ecological services—like cleaning the air, storing carbon and providing habitat. We’re talking about trees, of course. But human changes to the environment appear to be causing profound changes to trees around the world.
In a new study, scientists reviewed global research on trends in tree seedlings growth and death. They combined those data with an analysis of deforestation. And they found that worldwide, older trees are dying at a higher rate than in the past due to factors like rising air temperature, wildfires, drought and pathogens(病原菌).
“And most of the drivers of that decrease in large, old trees are increasing themselves, such as temperature is going up, droughts are more severe, wildfires, windstorms and deforestation are all on the increase—although variable across the globe—they’re generally increasing. And so for both the loss has already occurred, but we expect more continued loss of big, old trees.” said Nate McDowell, an earth scientist at Pacific Northwest National Lab, who was one of the study’s authors.
“So if we have an increasing rate of death, particularly of the larger, older trees, what’s left are the younger trees. So that’s why, on average, through the loss of bigger, older trees, our forests are becoming inherently(天生地) younger and shorter.”
This trend is a problem, because old trees are vitally important.
“For sure, the increase in death does limit the carbon storage of an ecosystem and can force the system to become a carbon source to the atmosphere. The second reason we care is from a biodiversity perspective: old trees tend to house a higher biodiversity than young forests do. And the third reason is aesthetic: as a society, we care about these trees. We have national parks named after these big trees. So there’s a personal reason for people to care about this as well.”
1. What has the new study found about the forests?| A．Forests are getting younger and shorter. |
| B．Many factors cause the death of big old trees. |
| C．Old trees are beneficial to humans in many ways. |
| D．The death of big old trees influences biodiversity. |
| A．The death rates of big old trees. |
| B．The trends in the death of big old trees. |
| C．The human changes to the environment. |
| D．The factors causing high death rate of old trees. |
| A．By giving examples. | B．By analyzing reasons. |
| C．By listing facts. | D．By providing figures. |
| A．To call on people to protect old trees. |
| B．To illustrate a phenomenon about old trees. |
| C．To share the findings of a new study about trees. |
| D．To analyze the reasons why some trees are dying faster. |
【推荐3】For many students today, distance learning has become the new normal. But distance learning means lots of screen time.
Research has shown that kids who spend a lot of time on screens are more likely to have various health problems and trouble with reading and language. Yet in the countries still suffering from the epidemic (流行病)，screens are the only safe way for many young people to learn or socialize. It's difficult for kids and teens to navigate this dilemma.
In one 2019 study, Taren Sanders, a health scientist at Australian Catholic University in North Sydney, looked at how kids spent their screen time. His group then investigated whether the type o£ screen time made a difference in health and school achievements. The researchers sorted screen time into five types: passive (such as watching a movie) , interactive (such as . playing a video game), social, educational or something else.
Educational screen time was linked to doing better in school and had no bad health effects. More passive screen time was linked to worse outcomes in health and school achievements, Sanders' group found, compared with the other categories. But the impact was quite small. Major problems showed up mainly in kids spending more than eight hours a day on screens.
The most serious problem caused by too much screen time is that people usually sit still while they are in front ,o£ a screen. "If students are spending all day sitting on screens, when are they moving?” asks Guerrero, who studies patterns of diseases. “Extended time sitting and not moving around leads to obesity, diabetes, heart disease and other health issues. So an important question to ask yourself is not how much screen time are you getting, but how active are you?"
Sanders agrees. "Overall, I'm not too concerned about the additional screen time kids are having because of distance learning," he says. “The things you should worry about: The amount of exercise they get and the way they spend their free time. "
1. What does the underlined word "navigate, in Paragraph 2 mean?| A．Handle. | B．Assume. | C．Observe. | D．Seize. |
| A．There are mainly five types of screen time. |
| B．Educational screen time damages kids' health. |
| C．Passive screen time has a major influence on kids. |
| D．Too much screen time is the major cause of problems. |
| A．The problem of lacking exercise. |
| B．Kids way of spending their free time. |
| C．The number of diseases related to screen time. |
| D．Distance learning causes additional screen time. |
| A．To guide parents to educate their kids. |
| B．To explain the finding of a new study. |
| C．To discuss the influence of screen time. |
| D．To analyse the effect of distance learning. |
