1 . Chinese scientists have identified a new protein that restricts HIV infection, a discovery that could pave the way for the development of new drugs against the virus. The protein, P-selectin glycoprotein ligand 1 (PSGL-1), which exists in human cells, can inhibit (抑制) the process by which HIV reproduces, according to research published in the science journal Nature Microbiology this month.
However, the study also showed that PSGL-1 can be negatively affected by Vpu — an accessory (附属) protein of HIV — which can neutralize the ability of PSGL-1 to resist HIV. Further research is under way to develop a drug that can inhibit the HIV protein so that PSGL-1 can restrict HIV, according to Tan Xu, a researcher at Tsinghua University's School of Pharmaceutical Sciences, a leading author of the study.
Several other proteins in human cells that could resist HIV have been discovered over the past 10 years, but the virus can also evade (避开) them. PSGL-1 shows particular promise in that it can inhibit HIV in multiple ways — especially by blocking the infectiousness of virus offspring, Tan said.
“We are starting to research into small molecule (分子) compounds in the hope of finding one that can restore PSGL-1’s anti-HIV function. In this way, we can develop a very effective antiviral drug for people with HIV/AIDS,” he said. Tan said it will require at least three to five years for the research to reach the preclinical stage, and more time after that before a clinical trial is possible. The research was conducted by researchers at Tsinghua University in Beijing, Fudan University in Shanghai and George Mason University in the United States.
Existing treatment methods for people with HIV/AIDS, which mostly rely on a combination of different drugs, can prevent the disease from progressing but cannot cure it, and long-term use of drugs can result in drug resistance.
An estimated 37 million people in the world live with HIV, according to the Joint United Nations Programme on HIV/AIDS. The study provides new leads to developing antiviral drugs, Tsinghua University said in a statement.
1. What can we learn about PSGL-1 from the passage?| A．Both the protein PSGL-1 and the protein Vpu are HIV proteins. |
| B．PSGL-1 can restrict the function of the protein Vpu. |
| C．PSGL-1’s molecule compounds have been identified. |
| D．The protein PSGL-1 functions better than others in resisting HIV. |
| A．The existing treatment for AIDS are far from perfect. |
| B．It will be a decade before the antiviral drugs is put on the market. |
| C．American scientists played a leading role in the research. |
| D．HIV/AIDS will no longer be a deadly problem owing to the new discovery. |
| A．There is a long way to go before curing AIDS. |
| B．More people are faced with the threat of HIV. |
| C．Chinese scientists are leading the way in curing AIDS. |
| D．A new protein to resist HIV was confirmed by scientists. |
| A．A guidebook. | B．A fiction. | C．A magazine. | D．A brochure. |
2 . Many people think that the world is about to step into the fourth industrial revolution. This time, machines can do a lot of work in the charge of human beings, even better than human beings. In the future, the world can be more efficient and enjoy cheaper services, but unemployment will become more common.
It raises a troubling question for all of us — when will a machine be able to do my job? Katja Grace, a research associate at the University of Oxford’s Future of Humanity Institute, and her colleagues from the AI Impacts project and the Machine Intelligence Research Institute, have surveyed 352 scientists and compiled (汇编) their answers into predictions about how long it may take for machines to outperform humans on various tasks.
The good news is that many of us will probably be safe in our jobs for some time to come. The researchers predict there is a 50% chance that machines will be capable of taking over all human jobs in 120 years.
“One of the biggest surprises was the overall lateness of the predictions,” says Grace. “I expected the amazing progress in machine learning in recent years, plus the fact that we were only talking to machine learning researchers, to make the estimates earlier.”
“I am a bit sceptical of some of the timelines given for tasks that involve physical manipulation (操纵),” says Jeremy Wyatt, professor of robotics and artificial intelligence at the University of Birmingham. “It is one thing doing it in the lab, and quite another having a robot that can do a job reliably in the real world better than a human.”
Manipulating physical objects in the real world — figuring out what to manipulate, and how, in a random, changing environment — is an incredibly complex job for a machine. Tasks that don’t involve physical manipulation are easier to teach.
Perhaps the hardest jobs for machines to perform are those that take years of training for humans to excel at. These often involve intuitive (直觉的) decision making, complex physical environments or abstract thinking — all things that computers struggle with.
1. Why did the researchers conduct the survey on the future role of machines?| A．To make it clear how machines can replace humans. |
| B．To find why machines can take the place of humans. |
| C．To explain humans will be substituted by machines. |
| D．To learn when machines may be superior to humans on jobs. |
| A．She thought the time would be totally uncertain despite the survey. |
| B．She thought the time would be later than predicted. |
| C．She thought the time would be earlier than predicted. |
| D．She thought machines would take over all the jobs in 120 years. |
| A．A robot can do a job reliably in the real world better than a human. |
| B．Tasks that don’t involve physical manipulation are quite complicated. |
| C．It is difficult for robots to finish the jobs related to physical manipulation. |
| D．He is sure of the timelines given for tasks that involve physical manipulation. |
3 . With nations preparing to spend billions to redesign their cities with a new focus on cycling, it's worth remembering how the invention of the bicycle changed societies all over the world.
The person generally credited with inventing the modern bicycle was an Englishman named John Kemp Starley. In 1885, the 30⁃year⁃old inventor began experimenting in his workshop with a chain⁃driven bicycle featuring two much smaller wheels. When it first appeared at a bicycle show in 1886, his invention was regarded as a curiosity. But two years later, when the next model was paired with the newly invented rubber tire—which not only cushioned the ride but also made the new bicycle about 30 percent faster—the result was magic.
For a few years in the 1890s, almost anyone wanted to learn to ride, and almost everyone did. The sultan of Zanzibar took up cycling. So did the czar of Russia. But it was the middle and working classes around the globe that truly made the bicycle their own. For the first time in history, the masses were able to come and go as they pleased. No more need for expensive horses and carriages.
The rocketing demand led hundreds of new companies around the world to offer their own versions. At the Stanley Bicycle Show in London in 1895, about 200 bicycle makers exhibited 3,000 models. One of the biggest makers was Columbia Bicycles, whose factory in Hartford, Connecticut, could turn out a bicycle a minute thanks to its automated assembly line (流水线)—a pioneering technology that one day would become the backbone of the automobile industry. By 1898, a third of all patent applications in the US were bicycle⁃related.
The bicycle even improved the human gene (基因) pool. Newly liberated young people rode around the countryside at will, meeting up in distant villages. Women were especially enthusiastic. They abandoned their troublesome skirts and took to the road in groups. Marriage records in England show a marked rise in inter⁃village marriages during the bicycle craze of the 1890s.
1. What can we know about John Kemp Starley's first model?| A．It was invented in 1888. | B．It had two bigger wheels. |
| C．It did not have rubber tires. | D．It was accepted immediately. |
| A．In the 1860s. | B．In the 1870s. | C．In the 1880s. | D．In the 1890s. |
| A．The fast⁃growing demand for bicycles. |
| B．The huge success of the bicycle industry. |
| C．The great convenience offered by bicycles. |
| D．The popularity of the newly invented bicycles. |
Tears are good for your eyes. In fact, without them, your eyes wouldn’t even be able to move. Some people say tears help us in other ways, too. Maybe you know someone who likes to watch sad movies in order to “have a good cry”. It hasn’t been proven, but tears may be good not only for your eyes but also for your emotional health as well.
We generally only notice tears when we cry, but we have them in our eyes all the time. Tears affect how we see the world while at the same time protecting our eyes from it. Without this liquid covering them, our eyes would be at risk of infection. In addition, we need tears in order to see. The cornea (角膜) of the eye does not have a perfectly smooth surface. Tears fill in the holes in the cornea and make it smooth so that we can see clearly. Without tears, the world would look very strange to us.
There are three types of tears, and they are called basal, reflex, and emotional tears. These three types are different not only in purpose but also in composition.
Tom Lutz, the author of Crying: The Natural and Cultural History of Tears, writes, “Throughout history, and in every culture, ... everyone everywhere cries at some time.” Even men and women who say they never cry can usually remember crying as children. Most of us probably think it’s normal for men or women to cry at certain times, and at such times, we may even encourage them to cry. For example, it’s no surprise when someone cries during a sad movie, and we often expect people to cry when a family member dies. However, we don’t always take this view of tears. Sometimes adults who cry — or even children who do — lose the respect of others. For example, what would you think of an adult who cried over losing a card game? Most people are aware of the social rules about when, where, and why it’s OK to cry. These rules generally differ for children and adults, and often for men and women. They depend on things such as family, culture, and religion, and they change over time.
Some people think it’s not just OK to cry but actually healthy to let the tears flow. Doctors in Greece over 2,500 years ago thought that tears came from the brain and that everyone needed to let them out. Today, many people still believe in getting tears out. They say that through crying, we get rid of emotions we have stored up, which is good for our mental health. Some people report that they feel better after crying. This could be because of the chemicals in emotional tears. One chemical is a type of endorphin, a painkiller that the body naturally produces. Emotional tears increase the amount of endorphin that gets to the brain because tears flow from the eye into the nose and pass to the brain that way. This painkiller may make a person less aware of sad or angry feelings, and that could explain why someone feels better after “a good cry”.
1. When do we have tears in our eyes?
2. How do tears help us see clearly?
3. How many kinds of tears do we have?
4. Please list at least two things that are related to the social rules of crying.
5. In which country did doctors over 2,500 years ago believe that tears came from the brain?
5 . 
Over eight million people live in London and it has about 26 million visitors each year. So what can you see in three days? Here are some must-see places.
DAY 1
THE RIVER THAMES is the heart of the city. There are 104 bridges—London Bridge and Tower Bridge are the most famous. Cross the new Millennium Bridge on foot. It’s London’s first bridge in 100 years.
SHAKESPEARE’S GLOBE THEATER was built in 1997! (A) In the summer you can see plays there. (B) You can shout during a performance just like in Shakespeare’s time! (C) Shakespeare is one of the greatest writers in the world. (D)Take an umbrella—there’s no roof!
TATE MODERN is the world’s largest modern art gallery. Located in an old power station, it’s a fantastic place to visit. However, don’t miss the British Museum with its collection of over 8 million objects. Follow the museum’s three-hour guide of the highlights.
DAY 2
THE HOUSES OF PARLIAMENT and BIG BEN are London’s landmarks, so don’t forget your camera. You can go inside and watch the politicians in the two chambers (会议厅) — the House of Commons and the House of Lords. Big Ben, which has four faces, sits at the top of the clock tower in the Houses of the Parliament. So no matter where you stand, you can read the face of the clock.
The King’s or the Queen’s official London home is BUCKINGHAM PALACE. It’s got 775 rooms! About 50,000 guests a year come to parties and events-sorry, invitation only! But you can see the Changing of the Guard.
THE LONDON EYE is the world’s largest sightseeing wheel and the most popular UK tourist attraction with about 3.5 million visitors a year. You can often see distances of 40 kilometers.
DAY 3
London’s cathedral, ST PAUL’S is 108 meters tall and over 300 years old. The entrance ticket isn’t cheap, but the cathedral is impressive, and the dome has got amazing views. At 309 meters tall, the new Shard building is the second tallest building in Europe. You can’t miss it!
Where’s the best place to go when it’s sunny or to relax? One of London’s many large parks such as HYDE PARK, KENSINGTON GARDENS or REGENT’S PARK. There isn’t time for LONDON ZOO, but it’s in Regent’s Park.
The best place for shopping is CAMDEN MARKET. You can find vintage (优质的) clothes, jewelry, great food and all sorts of things. Or go to Harrod’s, the world-famous department store. It’s got over 330different departments and an unbelievable Food Hall.
1. When was Shakespeare’s Globe Theater built?| A．In 1699. | B．In 1837. | C．In 1997. | D．In 2000. |
| A．On the bank of the River Thames. | B．In an old power station. |
| C．On Tower Bridge. | D．In Regent’s Park. |
| A．Businessmen. | B．Scholars. | C．Police officers. | D．Politicians. |
| A．The Millennium Bridge is the first bridge on the River Thames. |
| B．You can only attend the King’s or the Queen’s parties with an invitation. |
| C．St. Paul’s Cathedral in London is over 300 years old. |
| D．For many people Camden Market is the best shopping place in London. |
| A．In the summer you can see plays there. |
| B．You can shout during a performance just like in Shakespeare’s time! |
| C．Shakespeare is one of the greatest writers in the world. |
| D．Take an umbrella—there’s no roof! |
6 . Not only does Linda Greenlaw do one of the most dangerous jobs in the world, but she also does it extremely well. She has been described as “one of the best captains on the entire East coast”.
Linda was born and brought up on Isle au Haut, a tiny island ten kilometers off the coast of Maine, the USA. She fell in love with fishing as a child, and she worked on fishing boats during her summer breaks from college.
Linda has published four books to date.
But the world of fish and fishing is a man’s world.
| A．So why did she take up swordfishing in the first place? |
| B．And it’s not easy to find a word to describe Linda Greenlaw. |
| C．Before becoming a writer, she was the captain of a swordboat. |
| D．And that, in one of the leading countries in the fishing industry, is praise indeed. |
| E．Her first opportunity to go on a deep-sea fishing trip came when she was nineteen. |
| F．The swordfish is a very large fish that has a long swondlike beak formed by the bones of the upper jaw. |
| G．The first one, The Hungry Ocean, was top of the New York bestseller list for three months. |
7 . By now, we are all aware that social media has had a tremendous influence on our culture, in business, on the world-at-large. Social media websites revolutionized the way people communicate and socialize on the Web. However, aside from seeing your friend’s new baby on Facebook, or reading about Justin Bieber’s latest conflict with the law on Twitter, what are some of the real influences?
Social networks offer the opportunity for people to re-connect with their old friends and acquaintances, make new friends, share ideas and pictures, and many other activities. Users can keep pace with the latest global and local developments, and participate in campaigns and activities of their choices. Professionals use social media sites like LinkedIn to enhance their career and business development. Students can work together with their peers to improve their academic and communication skills.
Unfortunately, there are a few downsides too to social networking. If you are not careful, immoral people can target you for cyber bullying and disturbance on social sites. School children, young girls, and women can fall victim to online attacks which can create tension and suffering. If you are a victim of cyber bullying, do not take it lying down, but try to take appropriate legal action against the attacker.
Many companies have blocked social networks as addicted employees can distract themselves on such sites, instead of focusing on work. In fact, studies show that British companies have lost billions of dollars per year in productivity because of social media addiction among employees.
Also, what you carelessly post on the Internet can come back to trouble you. Revealing (泄露) personal information on social sites can make users vulnerable (易受伤害的) to crimes like identity theft, stalking, etc. Many companies perform a background check on the Internet before hiring an employee. If a potential employee has posted something embarrassing on social media, it can greatly affect their chances of getting the job. The same holds true for our relationships too, as our loved ones and friends may get to know if we post something undesirable on social networks.
Social media has its advantages and drawbacks as each coin has two sides. It is up to each user to use social sites wisely to enhance their professional and social life, and exercise caution to ensure they do not fall victim to online dangers.
1. Paragraph 2 mainly shows that social networks ________.| A．help students finish their homework | B．offer professionals good chances |
| C．benefit users in various ways | D．guide users to make right choices |
| A．forbid the use of social networks during work time |
| B．avoid posting embarrassing information |
| C．refuse to hire potential addicted employees |
| D．take legal action against the attackers |
| A．share experiences in using social media | B．remind people to wisely use social media |
| C．provide some advice on social problems | D．raise public awareness of social problems |
A． | B． |
C． | D． |
Blood: Water Mission is founded by the Grammy Award-winning band, Jars of Clay.
The results of our efforts paint a new picture in these communities. There has been a remarkable improvement in the water situation and community health.
It’s a beautiful story. We invite you to be a small part of a larger, beautiful story.
| A．Clean water wells have been built. |
| B．Most children get the opportunity to go to school. |
| C．There is a vital link between HIV/AIDS and clean water. |
| D．Meanwhile, the 1,000 Wells Project has expanded along the way. |
| E．Blood: Water Mission has also created social effects in the United States. |
| F．Blood: Water Mission has developed a close friendship with these communities. |
| G．There are many projects providing much-needed assistance to African communities. |
9 . Chinese speakers have got a new thing to be proud of. The language they are speaking is more difficult than English.
Understanding Chinese requires both sides of the brain, but English speakers listen with only half their minds on the job, UK scientists say.
UK psychologist Sophie Scott and researchers from hospitals in Oxford and London performed brain scans on volunteers as they listened to their native languages. When English speakers heard the sound of their language, the left parts of their brains lit up on screen. When Chinese speakers heard their native tongue, there was an action in both the right and left sides.
“We were very surprised to discover that people who speak different sorts of languages use their brains to decode speech in different ways.” said Scott.
The left side is normally connected with putting sounds together into words; the right with processing melody (音调) in music and speech, so this part “lights up” when English speakers hear music. The researchers do not yet know whether the right side is active in English speakers when they hear Chinese.
In Chinese, a different intonation (语调) delivers a different meaning, the syllable (音节) “ma”, for instance, can mean mother, hemp (麻), horse or scold according to its musical sound.
“Speech really is a complex sound,” said Scott. “As well as understanding words, the brain uses the way in which words are spoken, such as intonation and melody, to turn spoken language into meaning.”
“We think Chinese speakers interpret intonation and melody in the right sides of their brains to give correct meaning to the spoken words.”
The study suggests that language itself might affect the way the brain develops in a young child. It could explain why native speakers of English find it so extraordinary hard to learn Chinese.
1. What does the underlined “volunteers” in paragraph 3 refer to?| A．Chinese speakers. | B．English speakers. |
| C．People who speak different languages. | D．Researchers and Chinese and English speakers. |
| A．Music. | B．Meanings. |
| C．Intonation and melody. | D．The way the brain develops. |
| A．The left sides of their brains are not used for language. |
| B．They can hardly understand words when there is music. |
| C．The right sides of their brains are never used in childhood. |
| D．They can hardly understand words in the right side of the brain. |
| A．How the Brain Responds to Music |
| B．How the Brain Responds to Chinese |
| C．The Brain Responds to Languages Differently |
| D．The Two Sides of the Brain Work Differently |
10 . When drawing scientists. U. S. children now depict (描画) female scientists more often than ever, according to new Northwestern University research, which has analyzed five decades of “Draw-A-Scientist” studies conducted since the 1960s.
This change suggests that children’s stereotypes (刻板印象) linking science with men have weakened over time, said the researchers, consistent with more women becoming scientists and children’s media depicting more female scientists on television shows and other media.
In the first study, conducted between 1968 and 1979, less than one percent of 5,000 children drew an image resembling a woman when asked to draw a scientist. Almost all their artwork depicted men working with laboratory equipment, often with lab coats, glasses and facial hair.
But in later studies (1988 to 2019), 28 percent of children drew a female scientist, on average. In addition, both girls and boys drew female scientists more often over time, though girls overall drew female scientists much more often than boys.
“Our results suggest that children’s stereotypes change as women’s and men’s roles change in society.” said study lead author David Miller. “Children still draw more male than female scientists, but that is expected because women remain a minority in several science fields.”
The researchers also studied how children form stereotypes about scientists across child development. The results suggested children did not associate science with men until grade school; around age 5, they drew roughly equal percentages of male and female scientists. During elementary and middle school, the tendency to draw male scientists increased strongly with age. Older children were also more likely to draw scientists with lab coats and glasses, suggesting that children learn other stereotypes as they mature.
“These changes across children’s age likely reflect that children’s exposure to male scientists accumulates during development, even in recent years.” said Miller.
“To build on cultural changes, teachers and parents should present children with multiple examples of female scientists across many contexts such as science courses, television shows and informal conversations,” Miller said.
1. What is the change in children drawing scientists?| A．Children draw more male scientists. |
| B．Children draw more female scientists. |
| C．Girls draw more scientists than boys. |
| D．Children draw more female than male scientists. |
| A．It’s not surprising. | B．It’s not reasonable. |
| C．It’s unexpected. | D．It’s not acceptable. |
| A．How children develop their drawings. |
| B．How children’s stereotypes change with age. |
| C．Why children draw more male scientists. |
| D．What scientists look like in children’s drawings. |
| A．By encouraging children to attend science courses. |
| B．By encouraging children to become scientists in the future. |
| C．By giving children an example of drawing female scientists. |
| D．By making female scientists known to children in various situations. |
