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Finding fish is going to get harder as climate change continues to heat the world's oceans.A new study finds that warming seas over the past 80 years have reduced the sustainable catch of 124 species of fish and shellfish.Sustainable catch refers to the amount that can be harvested without doing long-term damage to the health of populations of some species.
  Overfishing has made that decline worse,researchers say.Overfishing refers to catching so many fish that the size of the population falls.In some parts of the world,such as the heavily fished Sea of Japan,the decrease is as high as 35 percent.That's a loss of more than one in every three fish.
  Researchers examined changes in 235 populations of fish and shell fish between 1930 and 2010．Those fish populations spread far apart across 38 ocean regions.Temperature changes vary from one ocean site to another.But on average over that time.Earth's sea-surface temperatures have risen by about half a degree Celsius.
  On average,that warming has caused the sustainable catch to drop by 4.1 percent,the study found.About 8 percent of the fish and shellfish populations the team studied saw losses as a result of the ocean warming.However,about 4 percent of some populations increased.That's because certain species have thrived in warmer waters.One example is a kind of black sea fish.It lives along the northeastern U．S．coast.As warming continues,these fish will reproduce faster until they reach their limit.
  About 3.2 billion people worldwide rely on seafood as a source of food.That means it's urgent for commercial fishing fleets and regulators to consider how climate change is affecting the health of all of those fish in the sea.



What does the new study discover？ ______

A. Overfishing is to blame for fish health.
B. Warming seas cause fewer fish and shellfish.
C. Seafood matters to people's health worldwide.
D. The living regions of fish and shellfish are different.

What does the underlined word "thrived" in Paragraph 4 probably mean？ ______

A. Survived narrowly.
B. Disappeared soon.
C. Decreased sharply.
D. Developed quickly.

What do we know about species of fish and shellfish？ ______

A. About 8 percent of them suffered from a great loss.
B. About 35 percent of them survived in the Sea of Japan.
C. About 3.2 billion species have been saved up to now.
D. About 80 species have died out because of warming seas.

From which is the text probably taken？ ______

A. A cooking guide.
B. A science magazine.
C. A news review.
D. A health brochure.

People have different ways of dealing with a common cold.Some take over-the-counter medicines such as aspirin （阿司匹林） while others try popular home remedies （疗法） like herbal tea or chicken soup.
  Yet here is the tough truth about the common cold：nothing really cures it.
  So why do people sometimes believe that their remedies work？ According to James Taylor,professor at the University of Washington,colds usually go away on their own in about a week,improving a little each day after symptoms peak,so it's easy to believe that it's medicine-rather than time -that deserves the credit（赞誉），USA Today reported.
  It still seems hard to believe that we can tackle much more serious diseases yet are powerless against something so common as a cold.Recently, scientists came closer to figuring out why.
  To understand it, you first need to know how antiviral （抗病毒的） drugs work.They attack the virus by attaching to and changing the surface structures（结构） of the virus.To do that, the drug must fit and lock into the virus like the right piece of a jigsaw （拼图） puzzle, which means scientists have to identify the virus and build a 3-D model to study its surface before they can design an antiviral drug that is effective enough.
  The two cold viruses that scientists had long known about were rhinovirus A and B. But they didn't find out about the existence of a third virus, rhinovirus C， until 2006. All three of them contribute to the common cold, but drugs that work well against rhinovirus A and B have little effect when used against C.
  "This explains most of the previous failures of drug trials against rhinovirus," study leader Professor Ann Palmenberg at University of Wisconsin-Madison, US， told Science Daily.
  Now, more than 10 years after the discovery of rhinovirus C， scientists have finally built a highly-detailed（高清的） 3-D model of the virus, showing that the surface of the virus is, as expected, different from that of other cold viruses.
  With the model in hand, hopefully a real cure for common cold is on its way. Soon, we may no longer have to waste our money on medicines that don't really work.



The author thinks traditional home remedies the common cold ______ .

A. are effective against
B. actually have no effect on
C. are slightly helpful in fighting
D. still need to be improved to work on

We can learn from the article that today's antiviral drugs work mainly by ______ .

A. absorbing different kinds of cold viruses at the same time
B. preventing colds from developing into serious diseases
C. changing the surface structures of known cold viruses
D. breaking up cold viruses directly

We can infer from the article that ______ .

A. scientists have already found a cure for the common cold
B. the surface of cold viruses looks quite similar
C. scientists were unaware of the existence of rhinovirus C until recently
D. understanding the structure of cold viruses is the key to developing an effective cure

What does the article mainly talk about？ ______

A. Why current cold remedies are useless.
B. How drug trials helped scientists find cures for the common cold.
C. How scientists found a previously unknown cold virus.
D. Why the new 3-D model of the cold virus is significant.

"An apple a day keeps the doctor away." Similarly, if we drink a little more water every day, we may find that we need to go to the doctor a lot less often. A healthy diet is made up of water and a great many different kinds of foods. We know that healthy foods like fruits, vegetables and fish, are important as they provide us with energy and fiber, without giving us too much fat and sugar. But why is water important？
  The human body needs water to survive. Water is important as it carries poisons and waste out of our bodies. However, doctors advise us to drink plenty of water, much more than the small amount we need to stay alive.
  Some doctors believe that water is important for our health in all kinds of ways. They believe that a great many illnesses and health problems start as a result of dehydration（脱水）-a lack of water in the body. Most people are dehydrated at least some of time, although they probably don't know it. It is surprising to learn that if we feel thirsty, we are already in the first stage of dehydration. In fact, we are advised to drink water before we feel thirsty.
  These doctors think that health problems such as headaches, high blood pressure and asthma（哮喘） could be helped if people drink more water. They also believe that drinking more water can help people who are overweight. Water contains no calories so it will not make us put on weight. If we drink water, we will probably drink less sugary soft drinks such as Coca-cola. Doctors also believe that drinking more water may stop people from overeating. They say that many people think that they are hungry when they are,in fact,thirsty. Doctors suggest, therefore, that we eat less food and drink more water. There are still many health problems that cannot be solved by drinking water, so we should not stop going to seeing the doctor completely. However, if we make a decision to drink water every day, we may find that we need to go to the doctor a lot less often.



From the text, we know water can carry ______ .

A. energy and fiber in our bodies
B. fruit, vegetables and fish in our bodies
C. sugar and fat out of our bodies
D. poisons and waste out of our bodies

Some doctors think that ______ .

A. some health problems are caused by a lack of water
B. water is not important for our health
C. we should go to the doctor less often
D. people eat too much sugar

Lack of water caused people to put on weight too much because ______ .

A. they think they are thirsty and eat less
B. they think they are hungry and eat too much
C. water has no calories
D. it makes them thirsty

Which of the following isn't mentioned in the passage？ ______

A. The amount of water a person should drink in a day.
B. Some healthy problems start because of a lack of water.
C. Drinking more water may stop people from overeating.
D. Fruit provides us with energy and fibre.

The connection between people and plants has long been the subject of scientific research. Recent studies have found positive effects. A study conducted in Youngstown, Ohio, for example, discovered that greener areas of the city experienced less crime. In another, employees were shown to be 15% more productive when their workplaces were decorated with houseplants.
  The engineers at the Massachusetts Institute of Technology（MIT）have taken it a step further changing the actual composition of plants in order to get them to perform diverse, even unusual functions. These include plants that have sensors printed onto their leaves to show when they're short of water and a plant that can detect harmful chemicals in groundwater. "We're thinking about how we can engineer plants to replace functions of the things that we use every day," explained Michael Strano,a professor of chemical engineering at MIT.
  One of his latest projects has been to make plants glow（发光）in experiments using some common vegetables. Strano's team found that they could create a faint light for three-and-a-half hours. The light,about one-thousandth of the amount needed to read by, is just a start. The technology,Strano said,could one day be used to light the rooms or even to turn trees into self-powered street lamps.
  In the future, the team hopes to develop a version of the technology that can be sprayed onto plant leaves in a one-off treatment that would last the plant's lifetime The engineers are also trying to develop an on and off "switch" where the glow would fade when exposed to daylight.
  Lighting accounts for about 7% of the total electricity consumed in the US. Since lighting is often far removed from the power source（电源）-such as the distance from a power plant to street lamps on a remote highway-a lot of energy is lost during transmission（传输）. Glowing plants could reduce this distance and therefore help save energy.



What is the first paragraph mainly about？ ______

A. A new study of different plants.
B. A big fall in crime rates.
C. Employees from various workplaces.
D. Benefits from green plants.

What is the function of the sensors printed on plant leaves by MIT engineer？ ______

A. To detect plants' lack of water.
B. To change compositions of plants.
C. To make the life of plants longer.
D. To test chemicals in plants.

What can we expect of the glowing plants in the future？ ______

A. They will speed up energy production.
B. They may transmit electricity to the home.
C. They might help reduce energy consumption.
D. They could take the place of power plants.

Which of the following can be the best title for the text？ ______

A. Can we grow more glowing plants？
B. How do we live with glowing plants？
C. Could glowing plants replace lamps？
D. How are glowing plants made pollution-free？

Sport is not only physically challenging, but can also be mentally challenging. Criticism from coaches, parents and other teammates, as well as pressure to win can create too much anxiety or stress for young athletes. Stress can be physical, emotional, or psychological and research has indicated that it can lead to burnout. Burnout has been described as dropping or quitting of an activity that was at one time enjoyable.
  The early years of development are critical years for learning about oneself. The sport setting is one where valuable experiences can take place. Young athletes can,for example,learn how to cooperate with others,make friends,and gain other social skills that will be used throughout their lives. Coaches and parents should be aware, at all times, that their feedback to youngsters can greatly affect their children. Youngsters may take their parents and coaches' criticisms to heart and find faults in themselves.
  Coaches and parents should also pay attention that youth sport participation does not become work for children. The outcome of the game should not be more important than the process of learning the sport and other life lessons. In today's youth sport setting young athletes may be worrying more about who will win instead of enjoying themselves and the sport. Following a game many parents and coaches focus on the outcome and find faults with youngsters' performances. Positive support should be provided regardless of the outcome. Research indicates that positive support motivates and has a greater effect on learning than criticism. Again,criticism can create high levels of stress, which can lead to burnout.



An effective way to prevent the burnout of young athletes is ______ .

A. to reduce their mental stress
B. to increase their sense of success
C. to make sport less competitive
D. to make sport more challenging

According to the passage, sport is positive for young people in that ______ .

A. it can provide valuable experiences for them
B. it enables them to find faults in themselves
C. it can help them learn more about society
D. it teaches them how to set realistic goals for themselves

Many coaches and parents are in the habit of criticizing young athletes ______ .

A. believing that criticism does good to their early development
B. in order to make them remember life's lessons
C. without realizing criticism may destroy their self-confidence
D. so as to put more pressure on them

According to the passage parents and coaches should ______ .

A. train children to cope with stress
B. help children to win every game
C. pay more attention to letting children enjoy sport
D. enable children to understand the positive aspect of sport

With the weather getting hot, bites caused by mosquitoes not only annoy people, but can result in many infectious diseases. Even when people wear long clothes, mosquitoes' complex biting mechanism enables them to bite some of them through.
  It would be great if clothing could be used to completely prevent people from getting bitten. Researchers tested graphene（石墨烯）， a material that is incredibly thin but really strong, in order to find out if it can make clothing resistant to mosquitoes.
  In the lab experiment, volunteers exposed a small patch of skin on their arm or hand to roughly 100 mosquitoes for five minutes at a time. Researchers tested three different situations： volunteers wearing no protection, wearing cheesecloth（薄纱棉布）， or wearing cheesecloth plus a thin graphene layer under it.
  A video camera was then used to record and quantify mosquitoes' behavior, including whether they landed on the skin, how long they stayed there, and whether they began to draw blood. The number of bites each volunteer got was also calculated based on how many swellings developed on their skin afterward. Finally,researchers dropped a little water or sweat on top of the graphene layer and studied the consequence, and they also tested a slightly different graphene layer called "reduced graphene".
  As a result, the number of mosquito bites on naked skin was the highest, about 16 on average； skin only protected by cheesecloth got the second, approximately 10 per five minutes' exposure. The exciting finding was that there was no swelling developing on skin covered by the thin graphene layer under cheesecloth,which means the material is effective at preventing mosquito bites. The mosquitoes landed on skin totally uncovered or covered in cheesecloth about 23 times on average,and stayed for one to two minutes. Comparatively, the mosquitoes landed on skin covered in the graphene layer fewer than 10 times, and the length of their stay was much shorter. Besides, water or sweat can ruin the graphene layer, which allows mosquitoes to bite through it. But fortunately, the number of mosquito bites in either dry or wet conditions can be lowered as long as the graphene material is improved to a certain extent.



Why did researchers conduct the experiment？ ______

A. To record the behavior of mosquitoes.
B. To find a substance to prevent mosquito bites.
C. To find a solution to stop infectious diseases.
D. To test graphene's effectiveness in preventing mosquito bites.

What does the underlined word "draw" in Pargaraph 4 probably mean？ ______

A. bleed
B. lose
C. test
D. suck

In which way did researchers draw a conclusion？ ______

A. By analyzing the reasons.
B. By comparing the statistics.
C. By classifying three situations.
D. By recording mosquitoes' behavior.

Which of the following shows how the text is developed？ ______

A. Cause-effect.
B. Opinion-fact.
C. Assumption-conclusion.
D. Phenomenon-evaluation.

In the Amazon rainforest of Venezuela, Yanomami hunter-gatherers exist on cassava, palm hearts and wild bananas. They also hunt frogs and monkeys using techniques that would have been familiar to their ancestors 11，000 years ago. The extraordinary continuity of their culture,and the fact that some of the groups have had little contact with outsiders,led biologists to wonder whether the Yanomami might reveal what the human digestive system looked like before industrialization supplied the world with processed foods and antibiotics.
  In 2019，researchers at the Icahn School of Medicine had a chance to find the answer in a previously unknown Yanomami village. Health workers collected feces（排泄物） from about 30 villagers. When the researchers cultured and analyzed microbes（微生物） from the feces in their laboratory,they discovered whole categories of bacteria that were absent from the guts（肠道） of people from industrialized countries. Even more strikingly, they found the microbial population in the average Westerner to be about half as diverse as the community inside these hunter-gatherers. The researchers realized that the microbes might have implications beyond basic science. People's microbial communities are believed to play a role in disorders like obesity, diabetes and Alzheimer's, which shorten lives and overburden health care systems. These disorders don't trouble these preindustrial hunter-gatherers, however. Therefore, researchers want to learn which microbes protect them and figure out how to reintroduce them in modern societies. It has the potential to affect health more profoundly than the discovery of the fabled Fountain of Youth.
But the opportunity might be more fleeting than youth itself. "The world is becoming urban so fast." says microbiologist Maria Gloria,co-author of the study that reveals the Yanomami microbiome（微生物群）. "Our lifestyles are killing microbial diversity." Although nobody has yet determined exactly what the Yanomami mystery bugs are doing and how they improve an individual's health,she believes that scientists need to collect and preserve as many microbes as possible for future breakthroughs. "We cannot afford to wait," she says, "or we'll have lost the high diversity of the human microbiome of traditional peoples before we understand how to use the microbiome to improve health."



What did the researchers find out in 2019？ ______

A. The hunter-gatherers had a different digestive system.
B. Microbial communities were to blame for many disorders.
C. People from industrialized countries had less diverse microbes.
D. Some categories of bacteria did not exist in the villagers' guts.

How did the researchers make their discovery？ ______

A. By collecting health data.
B. By conducting experiments.
C. By interviewing the villagers.
D. By recording the Yanomami's daily life.

What does the author mean by "the opportunity might be more fleeting than youth itself"？ ______

A. The opportunity seems more precious than youth.
B. The opportunity enables people to stay young forever.
C. The opportunity is of great significance to modern society.
D. The opportunity disappears so quickly that we cannot afford to miss it.

What can be inferred from the passage？ ______

A. We are close to solving the mystery of Yanomami microbiome.
B. Processed foods and antibiotics have changed human digestive system.
C. Treating diseases by introducing beneficial bacteria has been made possible.
D. The discovery of those microbes will help cure many life-threatening diseases.

The world food safety could be in danger because of a number of food production shocks（冲击） according to an Australian stud.
  The researchers from the University of Tasmania found that there were 226 shocks in the area of food production across 134 nations and the frequency has been increasing over the past 50 years.
  According to Cottrell, a researcher from the University of Tasmania, the main causes behind the shocks are different. For crops, extreme weather events such as floods and no rain for a long time play the biggest part. Weather also plays a role in livestock（家畜） production, but disease plays a bigger role. Disease also leads to aquaculture（水产业） shocks, while in the ocean most of the food shocks are caused by overfishing.
  "When we look at the food production systems, covering crops, livestock, fisheries and aquaculture," Cottrell said, "we find that crops and livestock are more easily affected than aquaculture. And some countries in South Asia are more frequently affected than others."
  The effects of production shocks reached far away from where they happened. When one means of food production is greatly reduced, it will cause unexpected results. "The India got a lot of food production shocks in crops and livestock, largely because of floods," Cottrell explained."If countries like India are shocked and the rice production is much smaller, they'll probably send less goods to another country. And that shock suddenly starts to affect all the trade partners of the major producers as well."
  According to what Cottrell said, while the international community faces a great challenge to these problems, steps taken now can help fight against unexpected shocks in the future."This can be done through measures such as food store systems so that they are better able to deal with the effect which is caused by problems such as climate change." said Cottrell.



What do we know about food production shocks？ ______

A. Their causes are different in different production areas.
B. Some diseases are the main cause.
C. Extreme weather is the biggest shock.
D. Overfishing is the main cause.

Which of the following is more frequently affected according to Cottrell？ ______

A. Livestock in Australia
B. Crops in Australian
C. Fisheries in India
D. Livestock in South Asia

Why does the writer mention Indian food production shocks？ ______

A. To show India sell a lot of crops to other countries.
B. To show the shocks can cause unexpected results.
C. To show Indian shocks are more often.
D. To show India has a lot of flood.

What can be a suitable title for the text？ ______

A. Results Caused by the Problem of Global Food Safety
B. Measures Solving the Problem of Global Food Safety
C. Production Shocks Threatening Global Food Safety
D. The Importance of Global Food Safety

For some people, walking or running outdoors is a great way to work out. What may not be so pleasant is seeing trash all over the ground. Well, some people are doing something about it. They are plogging!
  "Plogging" began in Sweden. The name combines the Swedish word "plocka," which means to pick up,and the word Jogging, which means to run slowly. A Swedish man named Erik, started the movement in 2016. On the World Environment Day website,Erik says that he moved to Stockholm from a small community in northern Sweden each day he would ride his bike to work. Concerned about the amount of trash and litter he saw each day on his way to work,he took matters into his own hands.
  Plogging, by that term, may have officially begun in Sweden. But many people who exercise outdoors have been doing this for years. Take Jeff Horowitz for example. He is a personal trainer in Washington,D.C. He often picks up trash while running outside. He even has turned it into a game；he will try to pick up the trash without stopping. "I didn't know it was a thing really. This is just my personal ethics（道德标准），where I go for a run and if I happen to see a piece of garbage lying around and it's within reach - it is a kind of a little test for me to see if I can grab it and throw it in a near trash can without stopping. And that way,I think,it gives me a little exercise and a little focus for my run. And it helps clean up the neighborhood," he announced.
  Today, plogging is an official activity, one that is becoming increasingly popular. Cities around the world now hold logging events,"I would just hope people would think twice before dropping a garbage on the ground. We have containers seems on every block. So,it's easy to put your garbage in the trash cans. I just think people should think about it a little bit more. I do hope one day there will not be a need for plogging." said an interviewee.



Which of the following can replace the underlined phrase "took matters into his own hands"？ ______

A. called on people to join him.
B. appealed to people to go green.
C. began to pick up the trash.
D. had the collected trash recycled.

What does the example of Jeff Horowitz tell us？ ______

A. Plogging comes naturally to joggers who care about the environment.
B. Plogging is an easy way to clean the environment.
C. It doesn't make any sense to joy without picking up trash.
D. It is better to clean up the neighborhood by plogging.

What is the idea that Logging events are meant to promote？ ______

A. Jogging is truly beneficial.
B. Trash cans should be within reach.
C. Littering is not acceptable.
D. Communities should be kept clean.

What can be a suitable title for the passage？ ______

A. New Exercise Enjoys unbelievable popularity
B. New Exercise Trend Also Helps Environment
C. Plogging - a Fashionable Way to clear waste
D. Plogging - an Exercise Originating in Sweden

Most of the new diseases we humans have faced in the past several decades have come from animals. The more we come into contact with wild animals, the more we risk a so-called disease "spillover" from animals to humans.
  As people move and wildlife move in response to a changing environment, humans and wildlife and animals will come in contact more regularly, said Jeanne Fair from the Los Alamos National Laboratory in New Mexico. Fair argues that by shifting（转移） animal habitats, climate change will also make the opportunities for disease spillover more frequent. "Everything is sort of shifting and will shift into the future as the environment changes through climate change," Fair said.
  Scientists, including climatologists and epidemiologists on Fairs team at Los Alamos are beginning to model how changes to the climate will impact the spread of infectious diseases. It's early days for this kind of research, but previous studies suggest that extreme weather has already played a role in at least one outbreak.Scientists say drought and deforestation have combined to force bats out of rainforests and into orchards （果园） in Malaysia to find food. Those bats, a common disease reservoir, then passed the Nipah virus through pigs to humans for the first time in the late 1990s.
  "Were going by the past data to really predict what's going to happen in the future," Fair said, "And so, anytime you increase that wildlife-human interface（外界）， that's sort of an emerging disease hot spot. And so, that's just increasing as we go forward."
  Jeffrey Shaman, head of the climate and health program at Columbia University's public health school,argues we don't yet know whether climate change will cause a net increase in infectious disease rates globally. For example, mosquitos carry disease that affects millions of people across the world every year. As their habitats expand in some parts of the world, they might contract diseases elsewhere. Shaman says what we know for certain about climate change is that it will make it harder to predict where disease outbreaks will pop up.



How does climate change affect the spread of disease according to Fair？ ______

A. By breaking animals' habits
B. By increasing animals' varieties.
C. By promoting animals' breeding.
D. By changing animals' living environment.

What is the example of bats for in paragraph 3？ ______

A. Explaining the influence of Nipah virus.
B. Proving the harm of bats to human beings.
C. Showing the effects of climate change on disease.
D. Presenting scientists' early study about the cause of disease.

What can we infer from Fairs words in paragraph 4？ ______

A. Humans should give up studying animals.
B. Past data can solve the problems in the future.
C. Disease hot spots will disappear if animals die out.
D. Frequent contact with animals can cause disease outbreaks

What could be the best title for the text？ ______

A. Climate Change and Disease Spillover
B. Animals' Interaction with Humans
C. Scientists' Prediction for Disease Outbreaks
D. Early Studies about Extreme Weather