【推荐2】After tracking flowers on a prairie (草原) in Minnesota for 21 years, scientists reported that the plants reproduce more successfully in the year following a carefully controlled burn. Understanding the relationship between prairie plants and fire is important for preserving this ecosystem which is becoming rapidly smaller, says Stuart Wagenius, a conservation scientist.

Fire provides an additional advantage for the narrow-leaved purple coneflower (紫锥花), as Wagenius and his colleagues say. To really bloom (开花), they need a little help: Enter the fire. Between 1996 and 2016, Wagenius says his team tracked nearly 8,000 purple coneflowers on the Staffanson Prairie Preserve. In 9 of those years, they conducted controlled burns over 400 times. “In the summer after a burn, many more plants flower,” Wagenius says. “It is just a huge flowering festival.”

Purple coneflowers and many other prairie plants were previously known to bloom energetically after fires. However, the researchers said that fire also stimulated purple coneflowers to bloom at the same time in the summer after a burn. This meant that instead of being unconnected, the purple coneflowers were surrounded by potential mates and went on to produce nearly double the number of seeds compared with other years. Wagenius says it’s not yet clear exactly how fires signal the flowers to get busy.

The new findings may help the people who manage prairies to better understand the different ways that fire affects the plants growing in these habitats, said Kathryn Yurkonis, a grassland ecologist who was not involved in the research. However, Yurkonis added, it remains to be shown how the fires influence the purple coneflower population. “This paper implies that making more seeds would mean more seeds would land on the soil and enter the population of plants — but they don’t actually examine that step,” she said. “I’d be curious to see whether this actually translates to more purple coneflowers.”

1. What is the basis for the research?

A．Prairies are easy to disappear.	B．Plants on a prairie are diverse.
C．Fire relates positively to prairie plants.	D．Without fire, flowers won’t bloom.

2. What does the author intend to convey with figures cited in paragraph two?

A．Wagenius’s team was committed indeed.

B．Samples of flowers were rich in number.

C．Time spent on the research was long.

D．The findings were relatively convincing.

3. What is paragraph 3 mainly about?

A．The result of plants being unconnected.

B．The influence of fires on prairie plants.

C．The process of prairie plants’ growing after fires.

D．The reason for plants’ blooming at the same time.

4. What is Kathryn Yurkonis’s attitude to the research finding?

A．Uninterested.

B．Prejudiced.

C．Objective.

D．Opposed.

【推荐3】A quick nap before arriving at your destination is normal, especially when you lack that much-needed sleep. But even if you feel energized, sleeping on buses and trains just seems to be a natural thing.     1     ? Here are some of the reasons.

    2    

Although buses and trains are not close to the comfort level of your couch or your bed, just being in a cozy(舒适的) enough position is sufficient to make you nod off. Sitting down, closing your eyes, and leaning your head a bit are enough to get you in a relaxed state.

Long periods of inactivity

On buses and trains, you don’t move around very much.     3     . Basically, you’re away from the things that keep your mind and your physical body busy. This inactivity also slows your brain activity down because there’s no stimulus to keep it awake.

White noise

    4    . It’s a consistent noise, like the hum of tires or the purring of the car. White noise masks distracting sounds, and is helpful for people who have trouble getting sleep. When you’re riding a vehicle, white noise is continuously emitted, making it easier for passengers to come to dreamland.

Increase in carbon dioxide in public transportation

Buses and trains get crowded every day with people going to and from work. Carbon dioxide increases when there are lots of people in a small space.     5     .

A．Comfortable seats

B．Lower the temperature

C．How to take a quick nap

D．This reduces oxygen to the brain and slows it down

E．So why do people fall asleep so easily on public transportation

F．Cars and other vehicles are a perfect environment that produces white noise

G．You just sit down and enjoy the scenery as the vehicle moves along the road

【推荐1】Butter coffee, also sometimes referred to as bulletproof coffee, is almost exactly what it sounds like. Take a cup of black coffee and drop a bit of butter into it. Though the name doesn't indicate this, you also need to add a little coconut oil. Upon hearing about butter coffee, people generally all into one of two camps. Either you are disgusted at the notion and determine never to try it or you are more laid-back and think "Sure, why not?"

If you are still puzzled about why this drink exists, here's a bit of backstory. In 2009, Dave Asprey, a businessman, launched and trademarked Bulletproof coffee. He got the idea during his travels in Tibet, where yak butter (酥油) tea is common. He marketed and sold the concept as a low-carbon, high-fat breakfast alternative that would help people lose weight and be energized.

Despite all of Asprey's claims, there are not many benefits to butter coffee, especially if anyone skips meals and replaces them with the drink. While cutting out carbohydrates (碳水化合物) may be good for people with type2 diabetes, a low-carbon diet is usually only recommended for a short period of time. And though the fat from the butter may keep you feeling full for a while, there are a number of downsides to adding a couple of tablespoons to your morning coffee.

Doctors point out that the amount of fat in butter coffee is higher than most recommended daily amounts. Additionally, a breakfast of butter and coffee does not contain nutrients that are essential to a healthy diet.

1. What does the author mean by "two camps" in the first paragraph?

A．The campsites where Asprey tried yak butter tea.

B．The areas where one can buy fresh butter coffee.

C．The two versions of butter coffee that are popular.

D．The opposing views people have about butter coffee.

2. Asprey got the inspiration for Bulletproof coffee when he was_________.

A．vacationing in Tibet

B．suffering from diabetes

C．starting his business

D．selling coffee beans overseas

3. Which of the following is mentioned as a supposed benefit of butter coffee?

A．It will help cure diabetes.

B．It serves as a meal replacement.

C．It may make people feel energetic.

D．It is good for those who need to put on weight.

4. What do doctors think of butter coffee?

A．The drink offers sufficient nutrients.

B．It is recommended as part of breakfast.

C．The drink is not fully healthy for people.

D．It should be avoided because of deadly chemicals.

【推荐2】Can snacking be a key element of a healthy lifestyle? If your first response is “No!”, here's a chance to update your opinions. Some of us were raised with the advice of “Never eat between meals.”, which can protect our teeth from sweets. Yet there can be significant advantages of snacking on healthy foods. Researchers have found that eating frequent mini-meals offers health benefits. Dr. David Jenkins and colleagues at the University of Toronto have reported some remarkable advantages.

In one study, participants were randomly divided into two groups and both groups were given the same type and amount of food over a two-week period. One group consumed three meals a day. For those having a “Nibbling Diet”, food was divided into 17 mini-meals a day. After two weeks, the nibblers had reduced their blood cholesterol(胆固醇) levels by more than 15 percent. Cortisol(皮质醇), a stress indicator,was reduced by 17 percent. Average serum insulin(血清胰岛素) levels of nibblers were reduced by 28 percent. With less insulin, the body is less likely to convert loads of calories into body fat.

Also, you may think eating concentrated sources of fat or sugar (or both) will pack the weight into your body. However, see below for some examples of healthy snacks:

Nuts are high in fat so keep portions moderate.

However, the fat comes with a wealth of minerals and protective substances. For growing youngsters, high-energy adults, athletes and those who have difficulty maintaining their weight, nuts are a great solution.

Dried fruits (raisins(葡萄干), currants, apricots) help you stock up on iron. If you tend to feel cold in winter, keep raisins handy. When your blood sugar drops, you'll have an instant remedy. Fresh fruit is also a great choice.

1. Why does the author propose a question at the beginning of the passage?

A．To raise the readers' awareness of refusing snacks.

B．To arouse the readers' interest in the topic.

C．To show the significance of healthy lifestyles.

D．To emphasize the importance of eating snacks.

2. What do the underlined words “Nibbling Diet” in Paragraph 2 refer to?

A．Not eating too much food at a time.

B．Eating many snacks at a time.

C．Eating food gently each time.

D．Eating food quickly each time.

3. How does the author convince readers to believe his opinion?

A．By explaining some concepts.

B．By using many experts' words.

C．By asking many specific questions.

D．By giving some examples.

4. Who can benefit from dried fruits in daily life?

A．An athlete who needs to maintain his weight.

B．A child who is eager to grow up quickly.

C．A girl who wants to warm herself in winter.

D．A patient who longs to decrease his blood sugar.

【推荐3】Scientists found a single dose of the protein Hila worked on lab rats. They said it showed “great promise as a future stroke treatment” but had not yet been tested in human trials.

The researchers travelled to Fraser Island in Australia to hunt for and capture three potentially deadly Australian funnel web spiders. They then took the spiders back to their laboratory “for milking”.

This involved coaxing the spider into releasing its venom, which can then be sucked up using pipettes(吸管). The scientists make a careful study of a protein in the venom and recreated a version of it in their lab.

They then injected this Hila into the lab rats. They found that the protein blocked acid-sensing ion channels in the brain-something the researchers say are key drivers of brain damage after stroke.

Professor Glenn King, who led the research, said, “We believe that we have, for the first time, found a way to minimize the effects of brain damage after a stroke. Hila even provides some protection to the core brain region most affected by oxygen deprivation, which is generally considered unrecoverable due to the rapid cell death caused by stroke.”

Dr. Kate Holmes, deputy director for Research at the Stroke Association, said, “We welcome any treatment that has the potential to reduce the damage caused by stroke, particularly if this can benefit people who are unable to arrive at hospital quickly.”

A stroke is a brain attack that happens when the blood supply to part of the brain is cut off or there is bleeding on the brain. Every two seconds, someone in the world will have a stoke. Stroke is the second most common cause of death, causing about6.7million deaths each year, one every five seconds. Almost one in every eight deaths is caused by stroke.

1. Which of the following is the last step of the research?

A．Inject the protein into lab rats.	B．Obtain the deadly spiders’ venom.
C．Catch three deadly spiders.	D．Recreate a version of the protein.

2. What does the underlined word in the third paragraph probably mean?

A．Forcing.

B．Trapping.

C．Requiring.

D．Feeding.

3. What is the main idea of the whole passage?

A．It is significant to acquire a medicine for stroke.

B．A promising cure for stroke is probably on the way.

C．Spiders are contributing to the treatment of strokes.

D．Stroke is the second biggest killer of in the world.

4. What purpose does the last paragraph serve?

A．To summarize the passage.	B．To introduce the topic.
C．To provide the background.	D．To support the argument.

【推荐1】Soot (煤灰) pollution is speeding up climate-driven melting in Antarctica, a new study suggests, raising questions about how to protect the delicate continent from the increasing number of humans who want to visit.

“It really makes us question, is our presence really needed?” says Alia Khan, one of the authors of the new study. “We have quite a large black carbon footprint in Antarctica, which is enhancing snow and ice melt.”

Black carbon is the leftover thing from burning plants or fossil fuels. Soot in Antarctica comes primarily from waste gases of cruise ships (游轮), vehicles, airplanes and electrical generators, although some pollution travels on the wind from other parts of the globe. The dark particles (微粒) coat white snow and absorb heat from the sun the way a black T-shirt does on a warm day. The blanket of dark bits speeds up melting that was already happening more quickly because of global warming. When snow and ice are uncovered, they reflect an enormous amount of sunlight before it can turn into heat.

“These are the mirrors on our planet,” says Sonia Nagorski, a scientist at the University of Alaska Southeast. “When those mirrors are covered in a film of dark bits, they are less reflective. That means more heat is trapped on Earth, speeding up melting and contributing to global warming.”

As a scientist who personally visits Antarctica every year, Khan says she is troubled by her own research results. On the one hand, she goes to Antarctica to collect crucial data about how quickly the snow and ice there are disappearing. “But then when we come to conclusions like this it really does make us think twice about how frequently we need to visit the continent,” she says, “and what kind of regulations should be placed on tourism as well.” That could mean requiring that cruise ships and vehicles be electric, for example, or limiting the number of visitors each year.

1. What are the feelings expressed in Khan’s words in paragraph 2?

A．Doubt and concern.

B．Confidence and courage.

C．Anger and disappointment.

D．Optimism and certainty.

2. Which of the following is a major source of soot in Antarctica?

A．Burnt plants.

B．Tourist vehicles.

C．Black carbon elsewhere.

D．Fossil fuels underneath Antarctica.

3. What does Nagorski say about soot?

A．It causes Antarctic surface temperature to rise.

B．It is increasing in amount because of wind.

C．It reflects a large volume of sunlight.

D．It is like a big mirror on Earth.

4. What might Khan do in the future?

A．Help design scientific research regulations.

B．Use electric cars for her daily transportation.

C．Collect more data about Antarctica.

D．Reduce her visits to Antarctica.

【推荐2】Carbon dioxide emissions from transportation are now thought as the top source of green—house gases. One of the most effective ways to reduce your carbon footprint is to reconsider how much, and how often, you travel.

Going car free for a year could save about 2.6 tons of carbon dioxide, according to a study from the University of British Columbia. How can you stop using a car? Try taking a train, bus or better yet, riding a bike.

But let’s be realistic. You will likely need to use a car this year. So, when you do, here are some tips to make your trip more climate—friendly. Driving efficiently can help to reduce emissions. Go easy on the gas and brakes and drive like you have an egg under your foot. Regularly service your car to keep it more efficient. Keeping your tires pumped correctly can reduce emissions. Low tire pressure will hurt your fuel economy. Air conditioning and frequent city driving can make emissions go up So cut down on these as often as possible. Use cruise control(定速巡航)on long drives—in most cases, this can help to save gas. Don’t weigh your car down with extra things that you don’t need on your trip.

Fly often? Taking one fewer long round—trip flight could reduce your personal carbon footprint significantly. If you use public transportation often and fly less, your carbon foot print might still be relatively sustainable, but if you drive and fly a lot, your emissions will be higher. If you can’t avoid flying, you can offset them by donating money to sustainable projects, such as supplying efficient stoves to rural homes, or projects which help farmers deal with crop waste environmentally.

1. What does the author think of going car free?

A．Efficient.

B．Costly.

C．Impractical.

D．Reliable.

2. Which can be adopted to save fuel of your car?

A．Maintaining your car properly.

B．Using cruise control in the city.

C．Stepping hard on the gas and brakes.

D．Getting rid of all the necessary loads.

3. What does the underlined word “offset” in paragraph 4 mean?

A．Put up with.

B．Team up with.

C．Set foot in.

D．Make up for.

4. Which is the best title for the text?

A．Lower carbon footprint in transportation

B．How to reduce your carbon footprint

C．Reduce carbon footprint by all means

D．How to save fuel when driving cars

【推荐3】Steel plays a significant role in the automobiles we drive and the transportation infrastructure that connects us. However, it also contributes to 7% of the world’s greenhouse gas emissions. In recognition of this, 45 nations made a pledge in 2021 to strive towards nearly zero-emission steel production within the next ten years.

However, how is it possible to produce the steel required for society with zero emissions?

A new study shows that if we are truly committed to reaching zero emissions, we must be prepared for a scenario where the amount of steel we can produce is lower. Japan has set a target for a 46% reduction in emissions from steel by 2030, and zero emissions by 2050. So far, the roadmap for achieving this relies heavily on future innovations in technology.

In the study, Dr. Takuma Watari, a Japanese researcher argues that there is no silver bullet. He says that current plans to cut carbon emissions underestimate how difficult it will be to develop CCS and hydrogen technologies and deploy them widely: “These technologies still face serious technical, economic, and social challenges, and have yet to be implemented at scale.

According to Dr. Watari, “zero-emission steel production is possible by 2050, but in limited quantity and quality compared to current total production. This is due to the limited availability of zero-emission compatible resources and downcycling practices of scrap steel.”

The implication is clear. It is not enough to rely on a technological silver bullet materializing to transform the supply of steel. We also need to look seriously at strategies to reduce demand by shifting our culture of steel use and improving our material efficiency.

Dr. Watari concludes that we do need to invest in technological innovations, but we cannot simply wait for them to appear. Instead, steel users need to prepare for a world where there is less steel available: “We do not deny the need to invest in innovative production technologies. Rather, what we want to highlight is that we should look for far more strategic options, instead of simply relying on silver bullet production technologies.”

1. Which is the key factor that affects zero-emission steel production?

A．Market requirement.	B．Scrap steel recycling.
C．Government support.	D．Technical improvement.

2. What does the underlined words silver bullet mean in Paragraph 4?

A．A good solution.

B．Precious treasure.

C．A deadly weapon.

D．Critical strike.

3. What’s Dr. Watari’s attitude towards the present steel use culture?

A．Supportive.

B．Ambiguous.

C．Unconcerned.

D．Critical.

4. What is the suggestion given to steel users?

A．Learning to live with less steel.

B．Producing steel without emissions.

C．Upcycling steel to remove impurities.

D．Stopping investing in technological innovations.