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Life-size sculptures existing underwater-accessible primarily to divers- are part tourist attraction,part ecological experiment in Jason deCaires Taylor's innovative art basis."Instead of seeing the world as a hidden,endless resource that we can treat how we want,I tried to change our relationship to it," says Taylor,a British environmentalist and sculptor.
A diver witnessing corals decline around the world,Taylor was inspired to explore how sculpture could be functional apart from aesthetics（审美学） by designing man-made reefs（珊瑚礁）.These underwater gardens created by Taylor call attention to the huge threats to ocean life- from rising sea temperatures to pollution- with breathtaking art exhibits that also double as artificial shelters for coral to regenerate and new ecosystems to boom.
About 25 percent of the ocean's marine life depends on healthy reefs for shelter and food,yet 40 percent of the world's coral reefs have been damaged over the last several decades due to factors such as global warming,overfishing and irresponsible tourism.
Creating the world's first underwater sculpture park in Grenada in 2006，Taylor has artfully highlighted the threats to our oceans while actively helping to create new life in them.
"A lot of my works are ordinary scenes you'd see in a terrestrial （陆地的） world,but when you drop them into a different word,you're able to think a little bit deeper and reflect in a different way," says Taylor.
"The Silent Evolution" is an undersea art exhibit off the Cancun coast.More than 400 life-size underwater statues were east from locals from a nearby fishing village who are now forever guarding their oceans.
Expected to open to the public in early 2021，Taylor's latest project aims to rebuild parts of the world's largest reef system.



Why does Jason deCaires Taylor design man-made reefs？ ______

A. To build more tourist attractions.
B. To conduct an ecological experiment.
C. To develop a hidden,endless resource.
D. To make man and nature live in harmony.

What makes the world's coral reefs at risk according to the text？ ______

A. The big threats from the divers.
B. The life-size underwater statues.
C. Natural disasters and human activities.
D. So may underwater sculpture parks.

What do we know from the text？ ______

A. Taylor uses the breathtaking art exhibits to double his art profits.
B. Undersea art exhibits aim to rebuild the whole world's reef system.
C. Taylor creates an underwater art world that's helping to save our oceans.
D. Witnessing corals decline around the world inspired Taylor's love for art.

Where is this text most likely from？ ______

A. A magazine.
B. A guidebook.
C. A novel.
D. A diary.

More than 1，500 feet below the surface of the ocean,it's darker than a moonless night.But even in this dark world,there's constant activity -including groups of Humboldt squids,each the size of a small adult human,darting around in search of fish.
"You can think of them as little rocket ships.They jet through the water.And they engage in these feeding frenzies.They're always looking out for an opportunity to eat." Stanford University biologist Ben Burford.He says feeding in a group requires careful navigation.
"These animals are pretty aggressive.So there's probably some risk to group living.Like,imagine driving in heavy traffic with a bunch of aggressive drivers.Thank goodness you have turn signals and brake lights and horns on your cars,because that prevents a lot of catastrophe from happening."
Burford thinks Humboldt squids communicate in the dark ocean by using their own form of signaling.They do it by turning their bodies into animated message boards.How？They can rapidly change their natural color patterns on their skin by contracting and relaxing their muscles.What's more,their bodies can be bright,or glow.
"They're creating a bioluminescent backlighting for their natural color patterns.So it becomes somewhat like an e-reader,something you can actually read in the dark.They're essentially just,you know,selectively revealing and concealing different parts of a glowing body,producing these patterns on top of a glowing body."
Burford suspected that the squids could be combining different natural color patterns to create complex signals. "So each of those elements could mean something.And they might have the potential to combine them to generate more meanings." To find out,his team attached cameras to remotely operated vehicles in order to study the squids' behavior. "We looked at how they arranged their patterns in sequence during prey-capture events."
Burford eventually hopes to do underwater experiments in which the squids are shown playbacks of their visual signaling-virtual glowing squids,if you will.Their reactions should be illuminating.



Which of the following can best describe Humboldt squids？ ______

A. Pretty but sensitive.
B. Mild but courageous.
C. Aggressive but cooperative.
D. Imaginative but cautious.

How do Humboldt squids communicate in the dark？ ______

A. By creating color patterns on their glowing body.
B. By touching other squids' bodies and muscles.
C. By navigating their way carefully in groups.
D. By examining their natural color selectively.

What did the researchers do to study the squids' behaviour？ ______

A. They operated the squids remotely.
B. They collected and analyzed signals.
C. They attached cameras to operable vehicles.
D. They conducted some underwater experiments.

Where can you most probably read this passage？ ______

A. In a travel guide book.
B. In a health magazine.
C. In a researchers' lab record.
D. In a scientific journal.

Hair loss is often be unwillingly accepted as a natural part of life.After all,most people,women included,will lose some or all of their hair as they get older.But when hair loss happens suddenly handfuls —it can be truly distressing.It can also be a signal of a health issue that needs to be addressed as soon as possible.
To understand why unexpected hair loss happens,it's useful to know the growth cycle of healthy hair.Usually,most of your hair is in a growing phase,during which strands lengthen by about 1.25 centimetres a month.This part of the cycle carries on for between two and eight years.After that,there's a middle phase,lasting about three weeks,during which the hair isn't getting longer but also isn't falling out.Finally,strands enter a resting phase,where the hair is loosened but sits in its follicle （毛囊）.Then,when the follicle begins to grow a new hair,the old one drops out.
Due to this cyclical process,we all lose up to 100 strands of hair each day. " At any one time,about ten per cent of our hair is in the falling out phase," explains Jennifer Jones,a dermatologist from London,UK，and an advisor to the British Association of Dermatologists.When that balance is disrupted，a person can have too much hair in the resting phase—and a few months later,he or she might find that a large amount comes out all at once.
Stress from sadness,divorce,or even moving house can cause hair loss.Another common cause is prescription drugs.In some cases,hair loss is subtle；other times,sufferers lose all their hair- including their body hair,eyebrows and eyelashes. "If you notice hair loss,you should discuss it with your doctor," says Jones. " We can often switch your medications." Treatment depends on the underlying cause.To discover that,a doctor might order blood tests,perform a small skin biopsy or examine the hairs under a microscope.If the loss is stress or drugs-related,it is usually temporary,and resolves within a few months without any intervention.



In which phase of its growth cycle will the hair get loosened？ ______

A. The growing phase.
B. The middle phase.
C. The resting phase.
D. The sitting phase.

What is the meaning of the underlined word " disrupted" in paragraph 3？ ______

A. Kept.
B. Broken.
C. Regained.
D. Developed.

What kind of life events is unlikely to cause hair loss？ ______

A. Getting a pet to keep you company.
B. Moving to a newly decorated house.
C. Getting divorced after years' suffering.
D. Taking drugs without your doctors' prescription.

Why will the doctor perform blood tests when you go to him for advice？ ______

A. To strengthen your hair quality.
B. To evaluate the conditions of your hair.
C. To perform a most suitable operation.
D. To work out the root cause effectively.

As paleontologists can tell, Neanderthals （尼安德特人）died out around 40，000 years ago. But they did not vanish from the Earth entirely. In the past decade it has become clear that Neanderthals mated with the ancestors of modern humans, and that some of those unions produced offspring （generations to follow）. The result is that almost half of the Neanderthal genome survives, spread in small quantities among most modern people's DNA. The exception is those with mostly African ancestors, for Neanderthals seem never to have lived in Africa.
Such genes have been associated with everything from hairiness to fatness. Many seem to be related to the immune system, and to affect the risk of developing diseases including lupus, Crohn's disease and diabetes.
A pair of recent papers suggest Covid-19 belongs on that list as well. Two long DNA strings, both inherited from Neanderthals, appear to have resistance or sensibility to severe Covid-19， depending on which is present.
The work was led by Hugo Zeberg and Svante Paabo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, whose researchers pioneered the study of Neanderthal DNA.
Their first paper, published in Nature in September, described one Neanderthal DNA string, known as a "haplotype"（单体型），which is associated with a higher risk of serious illness.
Having one copy of the haplotype, which is found on the third of the 46 chromosomes possessed by humans, doubles the chances of a trip to intensive care. Those unlucky enough to possess two copies, one from each parent, face an even higher risk.
That genetic bad luck is not evenly distributed. It is most common among people of South Asia, with 63 percent of the population of Bangladesh carrying at least one copy； and among Europeans, where the rate is around 16 percent. As expected, it is almost absent from Africa. More strikingly, it is also very rare in Eastern Asia.
Exactly what the haplotype does is not clear. One gene within it affects a protein that interacts with the cellular receptors （细胞受体）that SARS-CoV-2 （the virus which causes Covid-19）uses to enter cells and control them.
The haplotype is also thought to be involved in the production of signalling proteins,called cytokines,which help to regulate the immune system. An overly aggressive immune response is one mechanism by which Covid-19 kills.



Who are the most likely to carry the haplotype according to the study？ ______

A. Eastern Asians.
B. Africans.
C. Europeans.
D. South Asians.

What can we learn about the study？ ______

A. The haplotype is equally distributed among people in different races.
B. Covid-19 kills partly because the immune system responds to SARS-CoV-2 abnormally.
C. The haplotype appears to have resistance or sensibility to severe Covid-19.
D. People unlucky to have two copies of the haplotype are sure to suffer from serious illness.

What is the main idea of the last two paragraphs？ ______

A. Why the Neanderthal genome is related to a higher risk of serious illness.
B. What effects the haplotype has on different people in different races.
C. Why the haplotype makes people have a higher risk of Covid-19.
D. What the haplotype does to affect and regulate the immune system.

What will the author probably write in the next paragraph？ ______

A. The second study on Covid-19.
B. The previous study about Neanderthals.
C. The other Neanderthal DNA string.
D. The sensibility to severe Covid-19.

In June,11-year-old Nigerian ballet dancer Anthony Mmesoma Madu was filmed barefoot,spinning and leaping gracefully in the air and landing in concrete,rain puddles（水坑）.Just a few short months later,he has become an Internet star and gained a famous scholarship in America.
Madu thought he was being recorded for a study session by his ballet instructor,instead,the short video practicing his moves was posted on social media and has been shared widely across the world,with of his fans including Hollywood actors Cynthia Erivo and Viola Davis.
His dancing also caught the attention of Cynthia Harvey,the artistic director of the ABT Jacqueline Kennedy Onassis School of Dance in New York.Harvey was so impressed by his talent that she tracked him down and offered him a scholarship with the American Ballet Theatre where he will attend a summer school in 2021.
Madu says his interest in ballet developed after watching Barbie in the 12 Dancing Princesses,a 2006 cartoon about 12 princesses who share a passion for the dance. "When I was watching the cartoon,I told my mum that I want to do ballet," he said
He eventually got the chance to learn the dance after relocating to Ojo,a suburb（郊区）of Lagos with his mother,where they met Daniel Owoseni Ajala,founder of the Leap of Dance Academy.Ajala founded the dance academy in 2017 and has been teaching ballet for free to children who are unable to pay for a dance education since then.
When the self-taught instructor learned of Madu's desire to dance,he said he encouraged Madu's mother to let him sign up.It was during one of their sessions that he recorded Madu's dance video,but he never imagined that it would circulate rapidly.
"The video wasn't something we imagined to come out the way it did.It was just something that was supposed to show corrections of movements.It was bigger than I imagined,and I started getting calls.Celebrities were posting us," he said.



What can we know about Anthony Mmesoma Madu？ ______

A. He decided to apply for a scholarship.
B. He became one of Viola Davis' big fans.
C. He posted his short video on social media.
D. He impressed many people by his dancing.

When did Madu show interest in ballet？ ______

A. After attending a dance academy.
B. After moving to a suburb of Lagos.
C. After watching a lively cartoon.
D. After meeting Daniel Owoseni Ajala.

How can we describe Daniel Owoseni Ajala？ ______

A. Demanding but sympathetic.
B. Warm-hearted and respectable.
C. Stubborn but generous.
D. Creative and outstanding.

Which can be a suitable title for the text？ ______

A. A Non-profit Dance Academy
B. A Wonderful Dance Performance
C. A Self-taught Ballet Instructor
D. An 11-year-old Nigerian Ballet Boy

You may want to bring honey the next time you have a cold,a study says.That's because honey has been shown to provide better cough relief than some over-the-counter drugs,Oxford University researchers aid in findings published in BMJ Evidence-Based Medicine.
"Honey is more effective than usual care choices for improving upper respiratory tract infection（呼吸道感染）symptoms,particularly reducing cough frequency and cough severity," the scientists said in the findings.
Researchers said they reviewed 14 about upper respiratory tract infections,also known as common colds.Symptoms can include runny or stuffy nose,sneezing,sore throat and coughing,according to the Centers for Disease Control and Prevention（CDC）.
Four of the studies examined comparisons between honey and diphenhydramine，an antihistamine that can be used to relieve coughs,according to the U.S.government.It's sold at U.S.drugstores under several brand names and is combined with other ingredients（成分）in some cold medicines.
In their findings,Oxford scientists said honey was "significantly better than" diphenhydramine honey was "not significantly better" at cough relief when compared to another class of medicines,called dextromethorphan,according to a review of two studies with a combined 137 patients.Dextromethorphan is used to suppress（抑制）coughs.
Anyone sick with a cold should talk to a druggist or doctor about the best medicines for them,according to health officials."Over-the-counter medicines may provide temporary relief of symptoms,but they will not cure your illness," the CDC said on its website.
The CDC includes honey on its list of possible ways to suppress coughs.Other tips for feeling better from a cold include getting enough rest,breathing in steam and using saline spray,according to the CDC.



What's the author's purpose in writing this text？ ______

A. To prove honey's effectiveness in relieving cough.
B. To inform the readers how to better prevent colds.
C. To make a comparison between honey and medicines.
D. To give a description of symptoms of common colds.

What does the underlined word "diphenhydramine" in Paragraph 4 refer to？ ______

A. A cold symptom.
B. A sort of sweet food.
C. A kind of cold medicine.
D. A brand name of medicine.

What can we infer from CDC's advice？ ______

A. Honey safer choice for relief of cold symptoms.
B. Breathing in steam is a better way to suppress coughs.
C. Honey doesn't work for all the patients with a cold.
D. Over-the-counter medicines are a waste of money.

Where is this text most likely from？ ______

A. A history book.
B. An academic magazine.
C. A medicine textbook.
D. A science fiction.

While many people aren't getting enough calcium,new research cautions that some people may have the opposite problem：They could be getting too much.Americans spend more than﹩1 billion a year on calcium supplements in hopes of delaying osteoporosis,the brittle bone disease that cripples many elderly women and some men.Yet recent studies link calcium supplements to a higher risk of heart attacks.Last month,the U.S.Preventive Services Task Force issued a draft recommendation against taking calcium and vitamin D，saying there wasn't enough evidence of benefit to justify the risk.
For generations of Americans who grew up encouraged to drink milk to maintain strong bones,the reports raised troubling questions：Is calcium not so important after all？Are the supplements unsafe？And how much is too much？ "It's gotten very confusing but it doesn't need to be," says Ethel Siris,director of the Toni Stabile Osteoporosis Center in New York.How much calcium people need varies by age and gender. "Adults generally need 1，000 mg daily,rising to 1，200 mg for women over 50 and men over 70，according to guidelines issued in 2010.Children need 1，300 mg daily during the peak growing years of 9 to 18."
People also need sufficient levels of vitamin D to absorb the calcium.The IOM recommends 600 international units a day for most adults,and 800 daily after age 70，although many physicians recommend more.It is difficult to take in that much vitamin D from food sources,so experts say many people should take vitamin D in supplement form.
Getting adequate calcium from food is easier.For example,8 ounces of milk or 6 ounces of yogurt has 300 mg of calcium,and one cup of spinach has 270 mg.
But studies linking calcium supplements to heart attack have made experts more cautious of excess calcium than before.A study of 24，000 Germans published in the journal Heart last month,found that those who got their calcium exclusively from supplements were more than twice as likely to have a heart attack as those who took no supplements.
Exactly how calcium supplements might contribute to heart attacks baffles cardiologists. "Nobody has associated the calcium in your bloodstream with calcification in your arteries," says Nieca Goldberg,medical director of the Joan H.Tisch Center.Still,she says she now urges patients get their recommended calcium from food than from supplements to avoid possible problems.
Osteoporosis experts also urge patients not to take more than the recommended amount of calcium. "People should definitely stop taking two big calcium supplements a day," says Dr.Dawson-Hughes.Even if the risks remain unclear,taking more than the body can absorb doesn't benefit bones,"so it's not worth any risk." She adds.



According to the new studies,taking much calcium might ______ .

A. delay aging
B. build muscles
C. cause heart problems
D. cure bone diseases

What is Ethel Siris' opinion on taking calcium supplements？ ______

A. Taking calcium supplements is unsafe.
B. Adults need more calcium than children.
C. Age and gender determine taking calcium.
D. It is much safer to take calcium from food.

What does the underlined word "baffle" in Paragraph 6 mean？ ______

A. Interest.
B. Puzzle.
C. Amaze.
D. Frighten.

What can we learn from the passage？ ______

A. It is helpful to take two calcium supplements a day.
B. It is important to maintain strong bones for women.
C. It is unnecessary to take too much calcium supplement.
D. It is best to take calcium and vitamin D from supplement.

A self-powered robot inspired by a fish can survive the extreme pressures at the bottom of the ocean's deepest trench,the Mariana Trench,thanks to its soft body and distributed electronic system - and might help to explore the unexplored ocean.
Li and his team report that their robot that is made from soft materials can operate in the Mariana Trench.
Regular underwater instruments that are made of metals to survive the high pressures of the deep ocean are thick and heavy.But in Li and colleagues' robot,the delicate electronic components are fixed and placed separately in soft silicone（硅胶），which makes it much lighter.Besides,its softness allows it to squeeze into narrow spaces or to travel across uneven surfaces.
One of the difficulties faced by Li and co-workers was finding a way to protect the robot's electronic components from high pressures.Taking inspiration from the bones in the head of the hadal snailfish,the authors put the electronic components apart,rather than packing them together as is usually done in electronic devices.Laboratory tests showed that this design reduces the stress at the borders between components under pressure.The distributed electronics were then fixed in silicone into the robot.This method is more practical,and cheaper than other methods for protecting the electronics in deep-sea devices.
There is,however,more work to do before the ocean can be populated with robots of this type of design.
Li and co-workers' machine is slower than former underwater robots,and could easily be washed away.Its locomotor capabilities will also need to be improved for practical use.However,Li and colleagues' approach lays the foundations for future generations of deep-sea explorers.
These might include monitoring the ocean,cleaning up and preventing sea pollution or preserving marine biodiversity.More fundamentally,they could help researchers to explore the vast unexplored depths of the oceans.



What is the passage mainly about？ ______

A. New findings at the Mariana Trench.
B. A newly-designed underwater robot.
C. The importance of exploring the ocean.
D. The challenges faced by robot researchers.

In what way is the robot different from formerly reported robots？ ______

A. It is made of metal to survive the pressures.
B. It was tested in the laboratory and the ocean.
C. Its electronics are put in soft silicone apart.
D. It could help researchers to explore oceans.

What does the author think about this new type of robots？ ______

A. They are promising and will be put into use soon.
B. They are cheaper and lighter but may lead to sea pollution.
C. They are creative in design but need further improvement.
D. They are practical but have to be tested in different situations.

Who may benefit most from Li and his team's robot？ ______

A. Monitors.
B. Cleaners.
C. Robot producers.
D. Deep-sea scientists.

The different parts of a health care system have different focuses.A hospital's stroke（中风）unit monitors blood flow in the brain.The cardiac unit is interested in that same flow,but through and from the heart.Each collection of equipment and data is effective in its own field.Thus,like the story of blind men feeling an elephant,modern health care offers many separate pictures of a patient,but rarely a useful united one.
On top of all this,the instruments that doctors use to monitor health are often expensive,as is the training required to use them.That combined cost is too high for the medical system to scan regularly,for early signs of illness,so patients are at risk of heart disease or a stroke.
An unusual research project called AlzEye,run by Moorfields Eye Hospital in London,in cooperation with University College,London（UCL），may change this.It is attempting to use the eye as a window through which signals about the health of other organs could be discovered.The doctors in charge of it,Siegfried Wagner and Pearse Keane,are studying Moorfields' database of eye scans,which offers a detailed picture of the health of the retina（视网膜）.
The project will go a step further：With the information about other aspects of patients' health collected from other hospitals around England,doctors will be able to look for more accurate signs of disease through eye scans.
The Moorfields data set has lots of linked cases to work with--far more than any similar project.For instance,the UK Biobank,one of the world's leading collections of medical data about individual people,contains 631 cases of a "major cardiac adverse event".The Moorfields data contain about 12，000 such.The Biobank has data on about 1，500 stroke patients.Moorfields has 11，900.For the disease on which the Moorfields project will focus to start with dementia,the data set holds 15，100 cases.The only comparable study has 86.
Wagner and Keane are searching for patterns in the eye that show the emergence of disease elsewhere in the body.If such patterns could be recognized reliably,the potential impact would be huge.



Why does the author mention "the story of blind men feeling an elephant" in Paragraph 1？ ______

A. To claim the ineffectiveness of our health care system.
B. To tell the similarity in various health care units.
C. To explain the limitation of modern health care.
D. To show the complexity of patients' pictures

What does the underlined word "this" in Paragraph 3 refer to？ ______

A. The challenge of making advanced medical instruments.
B. The high risk of getting a heart disease or a stroke.
C. The inconvenience of modern health care service.
D. The incomplete and expensive health monitoring.

How does AlzEye work？ ______

A. By thoroughly examining one's body organs.
B. By identifying one's state of health through eye scans.
C. By helping doctors discover one's diseases of the eye.
D. By comparing the eye-scan data from different hospitals.

What can be inferred about the Moorfields's project from Paragraph 5？ ______

A. It takes advantage of abundantly available medical data.
B. It makes the collection of medical data more convenient.
C. It improves the Moorfields' competitiveness in the medical field.
D. It strengthens data sharing between the Moorfields and the Biobank.

Hardware in general,and smartphones in particular,have become a huge environmental and health problem in the Global South's landfill sites（垃圾填埋场）.
Electronic waste（e-waste）currently takes up 5 percent of all global waste,and it is set to increase rapidly as more of us own more than one smartphone,laptop and power bank.They end up in places like Agbogbloshie on the outskirts of Ghana's capital,Accra.It is the biggest e-waste dump in the world,where 10，000 informal workers walk through tons of abandoned goods as part of an informal recycling process.They risk their health searching for the precious metals that are found in abandoned smartphones.
But Agbogbloshie should not exist.The Basel Convention,a 1989 treaty,aims to prevent developed nations from unauthorized dumping of e-waste in less developed countries.The e-waste industry,however, circumvents the regulations by exporting e-waste labelled as "secondhand goods" to poor countries like Ghana,knowing full well that it is heading for a landfill site.
A recent report found Agbogbloshie contained some of the most dangerous chemicals.This is not surprising：smartphones contain chemicals like mercury（水银），lead and even arsenic（砷）.Reportedly,one egg from a free-range chicken in Agbogbloshie contained a certain chemical which can cause cancer and damage the immune system at a level that's about 220 times greater than a limit set by the European Food Safety Authority（EFSA）.Most worryingly,these poisonous chemicals are free to pollute the broader soil and water system.This should concern us all,since some of Ghana's top exports are cocoa and nuts.
Some governments have started to take responsibility for their consumers' waste.For example,Germany has started a project that includes a sustainable（可持续的）recycling system at Agbogbloshie,along with a health clinic for workers.However,governments cannot solve the problem alone,as there is an almost limitless consumer demand for hardware,especially when governments green policies are focused on issues like climate change.
Only the manufacturers can fix this.A more economically sustainable and politically possible solution is through encouraging hardware manufacturers to make the repair,reuse and recycling of hardware profitable,or at least cost-neutral.



What can we infer from Paragraph 2？ ______

A. Electronic products need improving urgently.
B. Electronic waste is too complex to get fully recycled.
C. Electronic waste requires more landfill sites across Ghana.
D. Electronic pollution is a burning question in Agbogbloshie.

What does the underlined word "circumvents" in Paragraph 3 mean？ ______

A. Tightens.
B. Abolishes.
C. Gets around.
D. Brings in.

What should be the biggest concern according to the text？ ______

A. The violation of EFSA's standards.
B. The lack of diversity in Ghana's exports.
C. The damage to chicken's immune system.
D. The threat of polluted food around the world.

What does the author think is the best solution to the e-waste problem？ ______

A. Manufacturers' developing a sustainable hardware economy.
B. Governments' adjusting their green policies about e-waste.
C. Reducing customers' demands for electronic products.
D. Letting governments take on the main responsibility.