Covid-19 is not the first disease to migrate from animals to humans. The Black Death of the 14 century was spread by fleas (跳蚤). The H1N1 virus behind the epidemic of 1918 originated in birds. The list goes on.
In the last two decades alone, we’ve been haunted by zoonotic (人畜共患的) outbreaks, including SARS, MERS, Ebola, bird flu, and most recently, COVID-19 and monkey-pox. Some researchers are beginning to call this era a Pandemicene. A study published in the journal Nature in April suggests that climate change may be to blame.
“The study comes from a simple idea,” says Colin Carlson, a global change biologist and a lead author of the paper. Climate change is making many habitats inhabitable. When animals migrate toward cooler climates, they introduce viruses to new environments. “That leads to interesting problems from a viral standpoint,” says Carlson.
To predict displacement patterns, Carlson and his colleagues taught machine-learning models the kinds of habitats used by different mammals. The modeling software then predicted, under a range of possible climate futures, where such conditions might be found in 2070, he explains. Many animals will head to cooler mountains, or to coastal regions with mild climates; Indonesia, the Philippines, India’s Rift Valley, and Sahel region are all expected to have sky-high human population densities and biodiversity levels by the year 2070, making them easy to be affected by outbreaks of zoonotic disease.
Carlson and his colleagues paired these predictions with a model that analyzes why different animals share viruses. The same flight capabilities that make bats excellent mosquito-hunters and seed-spreaders, for example, also make them more likely to transmit diseases. And while it’s easier for viruses to spread between closely related species, even viruses for our distant relatives can find purchase in us, given enough opportunities for infection.
Carlson and his colleagues estimate that by 2070, there will be at least 3,000 instances of novel cross-species infection. Not all will become pandemics, but some will.
1．Why is this era called “Pandemicene” by researchers in paragraph 2?| A．Many species are disappearing from the earth. |
| B．The climate change has become unpredictable. |
| C．Habitats for wildlife are destroyed by human activity. |
| D．Disease transmitted from animals are troubling humans. |
| A．Infectious diseases are rarely related to animals. |
| B．Migration of animals can lead to viral outbreaks. |
| C．Livable places for wild animals should be protected. |
| D．Global population and density will reach the peak in 2070. |
| A．Viruses can be spread between distantly related species. |
| B．Bats’ flight capabilities make them immune to diseases. |
| C．Wild creatures are given many opportunities to spread disease. |
| D．Humans may be infected with different viruses at the same time. |
| A．Colin Carlson, a Global Change. Biologist |
| B．Climate Change, a Reason for Animal Migration |
| C．Habitat Protection, an Effective Way to Biodiversity |
| D． Cross-species Infection, a Big Threat to Human Beings |
One day, Joyce Chancellor purchased an old diary at auction. She was
The inside front cover had the name and address of Mattie Leola. The diary chronicled (按事件发生顺序记载) events in a young professional woman’s life over a five-year period, including her college
Eventually the diary provided an important clue about Mattie’s possible descendants: an/a
After several
“Returning the diary to Mattie’s son was a/an
| A．attracted | B．challenged | C．assigned | D．shocked |
| A．identity | B．origin | C．family | D．ancestor |
| A．graduation | B．admission | C．application | D．employment |
| A．Pictures | B．Backgrounds | C．Dates | D．Clues |
| A．mistakes | B．history | C．money | D．preparations |
| A．belief | B．climate | C．recognition | D．support |
| A．lecture | B．context | C．edition | D．journal |
| A．forgive | B．inspire | C．marry | D．leave |
| A．located | B．contacted | C．changed | D．delivered |
| A．attempts | B．movements | C．appointments | D．events |
| A．deal | B．call | C．debate | D．meetup |
| A．secrets | B．diaries | C．promises | D．records |
| A．touched | B．impressive | C．anxious | D．addicted |
| A．tough | B．confusing | C．rewarding | D．awkward |
| A．solution | B．arrangements | C．effect | D．mark |
Alexander sang all the time. He sang in the shower, he sang while he did his homework, and he sang while he walked to school. He simply loved singing. One day during a break, he heard Kevin talking about the tryouts(选拔)for the City Choir(合唱团).
“Yeah, I’m attending the tryouts this weekend,” Kevin announced. “With my voice, I’m pretty much guaranteed a spot. I don’t even need any practice as I am so talented. Imagine they’ll want me to perform lots of solos(独唱),too.”
Everyone knew that Kevin had a fantastic singing voice. Normally, Alexander just ignored him, but he couldn’t help imagining himself as a member of the choir. Wouldn’t it be fun, he thought, to sing with other kids every day and have someone actually teach him about singing?
On the tryout day, Alexander took a deep breath, walked into the building, registered at a large table, and then waited nervously in the hallway. The only one who didn’t look nervous was Kevin. And why should he be? He has performed as a soloist many times. Alexander, on the other hand, had never taken a musical lesson in his life, much less had performed for an audience.
After a while, the choir director, Mr.Robeson, walked in and told the kids that they were to sing a song individually, sing as a group and answer some questions. Soon the individual test began. When Alexander stood on the stage, he tried to calm down and pretended he was singing in the shower. He felt satisfied when he was done, at least until Kevin’s turn came. As Kevin³s confident voice filled the room Alexander realized that he would never sound that good.
Next, Mr. Robeson put the kids into groups of four or five and asked them to sing together. Kevin’s group sang right before Alexander’s, and even with four other boys singing, Kevin’s voice clear and distinct; it seemed to reach the farthest corners of the room.
Then came the time for Alexander to sing with his group.
Finally Mr.Robeson told Alexander that he made it, not Kevin.
| A．He has just been back from South America. |
| B．He has been burnt for a few hours. |
| C．He has been doing school work all night. |
| D．He has been surfing the Internet for long. |
| A．To look for information for his project. |
| B．To meet new friends in the net chatroom. |
| C．To release pressure from heavy work. |
| D．To look for something interesting for pleasure. |
| A．Quite a few sites are just old event calendars. |
| B．It’s a waste of time to surf the Internet. |
| C．A lot of information can be found. |
| D．A lot of friends can be made on the Internet. |
| A．It takes long to find things because of many useless sites. |
| B．It’s hardly the best source of information available. |
| C．It is hard to start chatting with others in the chatroom. |
| D．People spend much time talking about other interests. |
It is a common sight on campus or in the streets: a young person rides by on an electric scooter, traveling quickly and proudly. But Beijing’s traffic authorities have said that starting on Sept.5, people who are caught riding electric scooters on public roads or bicycle lanes will be fined 10 yuan. They will also be given a warning not to use the vehicles on public roads again.
The announcement was made after traffic police in Shanghai started a campaign to get electric scooters off public roads, with police officers stopping riders because the scooters could cause traffic problems.
The Beijing Consumer Association said it had tested more than 20 electric scooters of different brands recently and found that most had substandard brakes. It added that 16 of the tested scooters could go faster than the maximum 20 km per hour set for electric bikes. According to the traffic police, people who ride electric scooters at certain speeds can easily bump into the vehicles in the vehicle lane and hurt people who walk in the bicycle lanes.
But seeing the benefits that electric scooters have brought to young people, experts are worried that the ban may take effect slowly.
Electric scooters are a great answer to the ‘last mile problem’ of getting from a public transport station to one’s home. They’re light enough to throw over your shoulder. They’re easy to ride just about anywhere and don’t need a lot of physical effort. The scooter can travel 25 km on one charge. It’s convenient and easy to control.
They are also good for environment. Unlike cars and buses, electric scooters produce no carbon dioxide, need no fuel and make almost no noise.
For many young people, they use them to copy cool celebrities they have seen in videos.
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On Thursdays, Charles Dandino becomes the conductor of an unusual kind of train. He leads what he calls a “ bike train, ” a group of cycling co-workers who band together for their 6-mile ride to work in the name of safety, as well as for fun and exercise.
After rising for several years, the percentage of commuters (通勤者) turning to bikes declined for the third year straight. In some cities, the decline was far more serious. In Tampa, Florida, and Cleveland, cycling to work dropped by at least 50 percent.
Experts offered several explanations for the nationwide decrease. Most obviously, lower gas prices and a stronger economy contributed to strong auto sales and less interest in cheaper alternatives, such as mass transit and bikes. The rise of ride-hailing services (叫车服务) such as Uber and electric scooters cut into bike commuting.
Around the country, city transportation officials wish there were more bicyclists like Dondino as they seek to cut traffic jams, promote health and identify alternatives to cars. Federal highway spending on bike and pedestrian-related improvements totaled $915.8 million this year. City officials tried to support bike commuters. Besides new bike lanes and trails, many cities added bike sharing programs, which allow cyclists to rent a bike to ride point-to-point or for the day.
For bike commuters, safety is a top consideration. It was one of the reasons that Dandino created his bicycle train. “ Riding bikes in a group is more thrilling and a joy to do, ” said Dandino. “ On the safety side, it makes us much more visible, and there’s strength in numbers. ”
Barbara Insua also rides regularly with Dandino’s bike train. She said she loved getting a workout on the way to her job. “ Uphill to work. Downhill home, ” she said. “ There are so many wonderful things about biking. ”
1．What was Charles Dandino’s main purpose to create the “ bike train ” ?| A．To protect the environment. | B．To reduce gas consuming. |
| C．To guarantee cyclists’ safety. | D．To support the officials. |
| A．Reasons for decline of cycling. | B．Contributions of a stronger economy. |
| C．Methods of being bike friendly. | D．Explanations for lower gas prices. |
| A．By cutting traffic jams. | B．By promoting alternative cars. |
| C．By building bike lanes. | D．By improving public transport. |
| A．To clarify a novel concept. | B．To provide more evidence. |
| C．To show a different opinion. | D．To offer background information. |
High-speed railways, electronic payments, shared bicycles and online shopping are China’s four new ways of life. They are most appealing to youths from 20 countries participating
In
Who has no regrets about things done in the past? Wouldn’t it be nice if, somehow, we could go back to change a couple of bad decisions? This sounds like science fiction.
The laws of physics prohibit traveling back in time for many reasons. If we did travel back in time and changed the course of events, we would be altering the course of history. An example often cited is the grandfather’s paradox (悖论): If your grandfather died when he was still a high school student, he wouldn’t have met your grandmother and your father and you wouldn’t exist.
Putting humans or consciousness traveling back in time aside for the moment, is there anything in science even similar? Surprisingly, yes. At the level of quantum particles (量子粒子), there is something called Wheeler’s delayed-choice experiments that show that actions in the present can influence the past. The experiments use something called the wave-particle duality (波粒二象性) of light and of matter. The fact that the physical nature of quantum objects is undetermined until it is measured. In other words, this means that a particle of light or of matter can behave either as a wave (spreading out in space) or as a particle (staying together) depending on the measuring devices. Long and ongoing discussions about the nature of quantum physics are still trying to work out what this actually means. Do our minds determine the nature of physical reality?
Should we offer food for thought for the future or the past? Unfortunately, these experiments say very little about how we could interfere with the past in events relevant to the human scale. Better to think carefully about decisions than to try to fix them backwards.
1．What’s the purpose of mentioning the paradox?| A．To show it is interesting. |
| B．To explain Wheeler’s tests. |
| C．To demonstrate time is different from what we have known. |
| D．To show it’s impossible to travel back in time. |
| A．Consciousness traveling back in time was tried in the experiments. |
| B．Different measuring devices have the same result. |
| C．More research is needed in the future. |
| D．These experiments can determine the nature of matter. |
| A．We should focus on the present. |
| B．The future food is more nutritious. |
| C．We can change the past from the experiments. |
| D．It is never too late to make up for mistakes. |
| A．Is changing the past wise? |
| B．Can we change the past? |
| C．Do our minds determine the future? |
| D．Do the laws of physics ban traveling back? |
My great-grandfather, my grandfather and my father are farmers, and so are all my family. My father has a fixed idea that I would become a farmer too. Although I respect him and am indeed skilled at doing some farm work, I don’t agree that I should automatically follow in my father’s footsteps.
When I was a teenager, my father happened to take me to an airport which belonged to one of his friends. It was the first time I had seen an aeroplane in real life. Knowing that I had never been on board, my father’s friend Tom offered me an opportunity to fly with him in his small aeroplane. I quickly accepted his offer! When we took off, I felt nervous but thrilled. Being up in the clouds and looking at the view below was unlike anything I had ever felt. I was just enjoying it. I assumed being a pilot would be the most awesome thing in the whole world. From that day a thought crept into my mind that I wanted to become a pilot, but I doubted whether my father would support me. After all, it was a totally different path from what he had planned for me. Therefore, I put the thought to the back of my mind, because I knew he would still insist on holding onto his previous idea.
Anyway, besides helping my father on the farm, I would frequently visit Tom’s airport. Gradually, I got familiar with every button and switch on the aircraft and I learned a lot about planes, such as how to fill the plane with fuel, how to check the engines and so on. But what I had learned just left me wanting more, so I decided to go to college to become a professional pilot.
This time I would not hide my desire any more.
At the graduation ceremony, with my father present, I, as “Best Pilot”, had to deliver a speech.
Early one weekend morning. I was sleeping like a log when the telephone rang. It was Grandma. She invited us to her home in the countryside. After a quick breakfast, Dad and I drove to Grandma's.
Once we arrived, we were both thrilled by the breathtaking landscape. The plum trees in the backyard were ripe with fruit, while millions of wildflowers colored the valley. Grandma prepared delicious lunch including her special homemade apple jam, which was my favorite. Talking and laughing, we didn't even notice that it was late in the afternoon. Though somewhat cooler than it had been that morning,Grandma suggested that we take her homemade wooden boat for a tour along the nearby river.
Seated in the boat, looking up at the sky. I felt like the clouds were greeting us cheerfully from above. In the vast fields, the golden trees were like brides in the sun. The breeze skimmed over the surface of the field, carrying the sweet smell of the flowers. "It is so nice to spend some quality time with family." Dad murmured. "It feels like we're on an adventure." I added. "It's been so much fun!"
While we were admiring the splendid setting around us. the weather started getting hot and humid again. At first, we ignored this change, but when dad looked up at the sky, he saw dark, low clouds were approaching us. Then a fierce gale（大风）sprang up. Lightning flashed within the black clouds, followed by a roar of thunder. "Row!" Dad shouted, trembling, "A tornado（龙卷风）is coming!"
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