Last year，NASA sent a supply spaceship to the International Space Station （ISS）.Its goods included thousands of tardigrades（緩步動(dòng)物）.These creatures，each small enough to fit on the tip of a pencil，can be found just about anywhere：in oceans，trees，and probably your backyard.Scientists say some tardigrades would continue to exist even if most other life-forms on Earth were wiped out.
Tardigrades are survivors，which makes them well suited for space travel.Some can take about a thousand times the amount of radiation（輻射） that would kill a human.Unlocking how they can do that is important if we hope to send people to Mars someday. "If we can learn the tricks that tardigrades use to protect themselves，" biologist Thomas Boothby says， "We could develop technologies that could protect humans.
The tardigrades on the ISS came from Boothby's lab at the University of Wyoming. Antecedent experiments exposed tardigrades to big doses（劑量） of radiation，and scientists made many amazing discoveries in this field.This time，Boothby wants to find out how they respond to low doses of radiation over a long period.That's the kind of exposure people living in space would get.
One way tardigrades protect themselves is by entering what's called a tun（桶）state.This adaptation lets them survive in places that dry out many times a year.Tardigrades dry up too.They curl（彎曲） up into tuns，or little balls，producing substances（物質(zhì)） that protect their cells from damage.Their metabolism（新陳代謝）shuts down.They "essentially stop to live，" Boothby says. "And they can stay like that for years or even decades."When water returns，tardigrades spring to life.
With this knowledge，scientists could develop foods that boost protective chemicals in astronauts' bodies.This might keep away from the effects of radiation.There is still lots of research to be done. "Right now，we're in the learning phase（階段），" Boothby says，adding that other scientists will build on his research. "That's just the way science works."
（1）Why did scientists send tardigrades to the ISS？ DD
A．To test their fitness for space travel.
B．To help do dangerous jobs on Mars.
C．To collect more radiation in space.
D．To understand their survival secrets.
（2）What does the underlined word "Antecedent" in paragraph 3 mean？ CC
A．Safe.
B．Secret.
C．Previous.
D．Frequent.
（3）Which of the following is tardigrades' feature of the tun state？ DD
A．They keep still to store more water.
B．They tend to move to dry places.
C．They become balls to save energy.
D．They seem to have no signs of life.
（4）What does Boothby think of his team's research on tardigrades？ BB
A．Fruitful
B．Pioneering
C．Dangerous
D．Unnecessary
【答案】D；C；D；B
【解答】
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發(fā)布：2024/5/27 14:0:0組卷：1引用：2難度：0.3
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1．Most of us spend our lives seeking the natural world.We go fishing，sit in the garden，have a picnic，live in the suburbs or go to the seaside.The most popular leisure activity in Britain is going for a walk.When joggers jog，they don't run on the streets.Every one of them tends to go to the park or the river.
But despite this，our children are growing up naturedeprived（剝奪）.I spent my boyhood climbing trees.These days，children are robbed of the ancient freedom，due to problems like crime，traffic，the loss of the open space and strange new ideas about what is best for children，that is to say，things that can be bought，rather than things that can be found.
The truth is to be found elsewhere.A study in the US：families had moved to better housing and the children were assessed for ADHD—Attention Deficit Hyperactivity Disorder（注意力缺陷多動(dòng)癥）.Those whose accommodation had more natural views showed an improvement of 19%；those who had the same improvement in material surroundings but no nice view improved just 4%.
ADHD is one of the great problems of modern childhood.One study after another indicates that contact with nature gives huge benefits to ADHD children.However，we spend money on drugs rather than on green places.
The life of old people is measurably better when they have access to nature.The increasing concern for the growing population of old people is in quality rather than quantity of years.And study after study finds that a garden is the single most important thing in finding that quality.Even problems with crime and aggressive behaviour are reduced when there is contact with the natural world.
We need the wild world.It is essential to our wellbeing，our health and our happiness.
（1）According to the author，people enjoyto seek nature.
A．jogging on the street
B．running in the gym
C．shopping in the supermarket
D．sitting in the garden
（2）From the second paragraph，we can see that.
A．Children don't want to approach nature
B．children probably spend less time in nature nowadays
C．climbing trees will certainly do good to the children
D．children tend to be happier as a result of their material satisfaction
（3）In what way do people benefit from their contact with nature？
A．Children with ADHD can be cured.
B．Children's performance at school is greatly improved.
C．Problems with crime and violent behavior will easily be solved.
D．A garden nearby improves the quality of old people's life.
（4）what is the main idea of this passage？
A．Access to nature improves our life.
B．Nature treats children for ADHD.
C．Getting close to nature reduces crime.
D．Man can't live without natural areas.發(fā)布：2025/1/6 16:30:6組卷：0引用：1難度：0.5 -
2．It is widely believed that biodiversity（生物多樣性）is promoted to save species.But in reality species exist only as part of ecosystems and cannot survive unless their ecosystems are protected along with as much as possible of the diversity they contain.
Protecting habitats（棲息地）is important for keeping biodiversity.In 2003，over 102，000 habitats covering nearly 19 million square kilometres，or 11.5% of the world's land surface，were under some form of protection.Though this is a great improvement since 1962，when just 1，000 protected habitats were listed，it is still not considered enough to stop the ecocide that is endangering the world's biodiversity.
For a number of environmentalist，protecting the world's 25 biodiversity hotspots（熱點(diǎn)地區(qū)）is critical to saving habitats and species.But many hotspots are endangered already，having lost up to three-quarters of their original plants.
The poor state of most biodiversity hotspots results directly from population growth and migration（遷移） into these areas.A study found that by the mid-1990s around 1.1 billion people lived in these hotspots.Moreover，the annual population growth rate in these areas was 1.8%，higher than the global average of 1.4%.The PAI report concluded that human-related environmental changes will continue to put pressure on hotspots.Therefore，keeping biodiversity requires paying close attention to population size.
Protecting hotspots is not simply a matter of putting up fences and employing guards.The best results are achieved when local people are educated about the value of wildlife，and actually gain a share of the benefits from eco-tourism.Only then do they have a chance to see the benefits of protecting hotpots.
（1）What can we infer from paragraph 1？
A．The loss of any species can affect humans.
B．Endangered species are paid more attention to by humans.
C．Species can still survive when their ecosystems are destroyed.
D．Ecosystem protection is as important as diversity protection.
（2）What does the underlined word "ecocide" in paragraph 2 mean？
A．Ecosystem protection.
B．Reduction of the number of species.
C．Serious damage to habitats.
D．Habitats protection.
（3）What's the direct cause of the terrible state of the hotspots？
A．Population growth in hotpots.
B．Migration out of these areas.
C．Global warming.
D．The global average population growth rate.
（4）What's the author's opinion on protecting the hotspots？
A．It's simple to carry out.
B．It leads to the increase of tourists.
C．It's closely connected with local people.
D．It suggests that the local people are well educated.發(fā)布：2025/1/6 16:30:6組卷：0引用：1難度：0.5 -
3．International students who stayed in the US as their classes moved online during the COVID may be forced to leave，following guidelines of the US Immigration and Customs Enforcement published due to the pandemic（流行病）.
"You know I don't want to put my family at risk，I don't want to put myself at risk to travel during a pandemic and go back to Pakistan，and even if I could delay the program for a year，it is not certain that I will get the visa again." said a Pakistani student.
Many students say they need to be in the US for more than attending cljye.ais.As a PhD student，the library is an extremely important resource for them，although it is because of COVED that those services have been closed，which means even this advantage is gone.
"You know more than 90% of the international students who were studying the US when COVID-19 hit and college campuses were closed have to remain in the US and this creates such trouble in their lives and such uncertainty that is unreasonable." said a lady from a university.
International students staving in the United States say the new ruling has disturbed their plans to return. "I know it is a fact that when it comes to rules，guidelines，laws and stuff like that，international students are sort of treated as low-level citizens.Even I can't even use the word "citizen" to begin with because that's what they make clear we are not."
The government said that the policy speaks for itself and that online coursework is not worth a visa.So far，not any sign of change has been within sight.As students are waiting for the policy to improve，their fall programming and their future remain in limbo.
（1）Why would international students prefer to stay in the US during the pandemic？
A．They couldn't delay the program for a year.
B．They can make full use of the library resource.
C．They wouldn't bring any potential danger to their family.
D．They can learn better with their classes moved online.
（2）What do international students staying in the United States think of the new rule？
A．The new rule treats them as American citizens.
B．The new rule shows great unreasonable opinion against them.
C．The new rule guides them to plan to return to the US.
D．The new rule treats them like low-level students in school.
（3）What is the government's attitude towards the new rule？
A．Favorable.
B．Neutral（中立）.
C．Unfavorable.
D．Unclear.
（4）What does the underlined phrase "in limbo" in the last paragraph mean？
A．Horrible.
B．Flexible.
C．Uncertain.
D．Unbelievable.發(fā)布：2025/1/6 15:30:8組卷：0引用：1難度：0.5
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