The world is being covered by plastic.In China，the amount of plastic waste rose into 14 million kilograms last year，but only about 9% was recycled.Over 1.32 million kilograms of plastic found its way into the world's oceans，which caused serious pollution.Luckily，researchers have found a special kind of bacteria which can help break down plastic recently.
The bacteria are so small that we need a microscope （顯微鏡） to see them.They can "eat" plastic by changing its chemicals into something that will help them grow.The secret to this is enzymes （酶）.Bacteria uses enzymes to cause chemical changes.
In 2012，in the decaying （腐爛的） leaves，scientists discovered an enzyme called LCC that slowly broke down PET plastic.Most people know PET plastic.It is used in water and soda bottles.Most PET is thrown away，but even when it is recycled，it can't be made into new bottles.Compared with other 100，000 enzymes，it was the best at breaking down PET.
To improve LCC，scientists studied the enzyme and the way it broke down the PET.By testing thousands of small changes to the enzyme，they found a new kind of LCC．It can be alive at higher temperatures，eat PET very quickly and make most PET plastic reusable.Scientists were satisfied with the result.When the environment was just right，the new LCC was able to break down 90% of the PET in just ten hours.The old enzyme took about 20 hours and only broke down half of the PET.
（1）How many plastic products are recycled in China last year？ CC
A．About 1.32 million kilograms.
B．About 14 million kilograms.
C．About 1.26 million kilograms.
（2）Which statement is TRUE about the bacteria？ CC
A．Bacteria can be seen with our eyes directly.
B．Bacteria can't be used to break down plastic.
C．Enzymes help bacteria change chemicals in plastic.
（3）From Paragraph 3，we can know CC.
A．most PET plastic could be made into new bottles again
B．a(chǎn)n enzyme called LCC was found in PET plastic in 2012
C．LCC was found the best at breaking down PET plastic
（4）Compared with the old LCC，which is NOT the advantage of the new kind of LCC？ BB
A．It can be alive at higher temperatures.
B．It can make all the PET plastic reusable.
C．It can break down PET plastic in a faster way.
（5）Where can we probably read this passage？ BB
A．In a storybook.
B．In a science report.
C．In an advertisement.
【答案】C；C；C；B；B
【解答】
【點(diǎn)評(píng)】
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發(fā)布：2024/12/3 9:30:3組卷：11引用：4難度：0.6
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1．Is there intelligent （有智力的） life on other planets？For years，scientists said "no" or "we don't know"．But today this is changing．Seth Shostak and Alexandra Barnett are astronomers （天文學(xué)家）．They believe intelligent life exists （存在） somewhere in the universe．They also think we will soon contact these beings （人；生物）．
Why do Shostak and Barnett think intelligent life exists on other planets？The first reason is time．Scientists believe the universe is about 12 billion years old． "This is long enough for other planets to have intelligent life，" say Shostak and Barnett．The second reason is size-the universe is huge． "Tools like the Hubble Telescope （哈勃望遠(yuǎn)鏡） have shown that there are at least 100 billion galaxies，" says Shostak． "And our galaxy，the Milky Way，has at least 100 billion stars．Some planets going around these stars might be similar to Earth．"
In the past，it was hard to look for signs of intelligent life in the universe．But now，powerful telescopes （高倍望遠(yuǎn)鏡） allow scientists to discover smaller planets．These planets might have intelligent life．
Have beings from space already visited Earth？ "Probably not，" says Shostak．However，intelligent beings may contact us in other way，such as radio signals （信號(hào)）．In fact，they may be trying to communicate with us now，but we don't have the right tools to receive their messages．However，this is changing．By 2025，we could make contact with other life forms in our universe and we might help each other．
（1）Seth Shostak and Alexandra Barnett are．
A．a(chǎn)stronomers
B．farmers
C．singers
D．drivers
（2）Why was it hard to look for signs of intelligent life in the universe in the past？
A．There were not any smaller planets．
B．The Milky Way didn't exist at that time．
C．The astronomers were not interested in them．
D．There were not any powerful telescopes．
（3）What is the best title for Paragraph 2？
A．The Age and Size of Earth
B．Why Intelligent Life Might Exist
C．Our Galaxy：The Milky Way
D．Earth：The Only Planet with Intelligent Life
（4）What does the underlined phrase "life forms" in the last paragraph mean？
A．messages
B．tools
C．intelligent beings
D．radio signals發(fā)布：2024/12/27 12:0:1組卷：58引用：5難度：0.3 -
2．Can Training Your Working Memory Make You Smarter？ We would all like to increase our cognitive （認(rèn)知的） ability beyond the limits set by Mother Nature.So it's no wonder that brain-training programs — which focus on training our working memory — are a multibillion-dollar industry.But can this kind of training really make us smarter？
Cognitive training sees the brain as a kind of muscle （肌肉） that can be made stronger with the right kind of practice.Although people did much research，there has been no agreement about its effectiveness.Some think that cognitive training increases some cognitive abilities，while others less hopeful.
Yet we do know that some cognitive skills probably go together and are predictors of real-life skills such as work performance.Thus，training one cognitive skill might lead to an improvement in many other cognitive and non-cognitive skills.That is the key hypothesis （假設(shè)） on which working-memory training is based.
To test this hypothesis，we examined all the studies about working-memory training.The results were very clear.Working-memory training did not show any effect on children's fluid intelligence （流體智力），a person's ability to solve new problems and get used to new sjye.aiuations.It didn't influence their educational achievement or other cognitive abilities，eijye.air.The only dependable effect was that children got better at what they were trained to do.So performing working memory tasks does seem to make you better at doing them.However，the fact that participants （參與者） got better at such tasks does not necessarily mean that their working memory ability increased.They may just have learnt how to perform that type of task.
The results do show that the use of working-memory training programs as an educational tool is useless.Beyond working-memory training，other recent studies have shown the limitations of different types of cognitive training.
However，these negative （負(fù)面的） results must not discourage us from training our cognitive and non-cognitive skills.We just have to realize the actual limitations of such practice in areas outside what we are actually training.But that doesn't mean we shouldn't do it — the most efficient way to develop a skill is，after all，to train that skill.
（1）According to the passage，cognitive training probably.
A．benefit the training companies
B．balance the learning skills
C．make us stronger through practice
D．help the children get good results
（2）Children taking part in the experiments were able to.
A．be familiar with new situations quickly
B．get greater educational achievements
C．succeed when they solve real life problems
D．do better in the field that they were trained in
（3）What is the writer's opinion on the cognitive training？
A．The cognitive training is a useful experiment.
B．The cognitive training can't make us smarter.
C．The cognitive training challenge the children's skills.
D．The experiment is helpful to children's cognitive skills.發(fā)布：2024/12/27 14:0:2組卷：27引用：3難度：0.5 -
3．A new technology is going to change our world in many ways．Yes，it's 5 G．It will bring us a much faster speed and wider coverage（覆蓋）．
With 5 G，__▲___．Most of us spend all day at school or work．After a long and busy day，all we want to do is to return to a comfortable home Smart technology can tum any house into a nicer place to live in．Everything in the house can be connected through smart technology．For example，a smart trash bin （垃圾桶） can record what you've thrown away and then order more of what you need．
There are also roads equipped with （配套）5 G technology to provide smart services．For example，they can tell you where the nearest gas station （加油站） is．These roads can also be used to control the traffic．
Smart schools will be the schools of the 21st century．5 G can make our school life more convenient．For example，many students enjoy talking to the al robots that were made by universities These AI robots are like personal helpers for students．Students can ask them questions whether or not a class is cancelled．
While everyone is excited for the speed of 5 G，the technology may also have some disadvantages．For one thing，people have to buy 5 G phones．For another，there might be privacy （隱私） problems．
（1）About 5 G，which of the following is NOT TRUE？
A．It will bring us a wider coverage
B．It will be only used at home．
C．It will bring us a much faster speed
D．It will change our world in many ways．
（2）Which of the following can be put in the__▲__？
A．our life will get worse
B．we can stay at home every day
C．homes will become smarter
D．trash bin can be very smart
（3）According to the passage，roads equipped with 5 G technology can．
A．only help to control the traffic
B．order more of what you need
C．make our school life convenient
D．tell us where the nearest gas station is
（4）If we put the passage into three parts，which of the following is the best？
（①=Para1 ②=Para.2 ③=Para.3 ④=Para4 ⑤Para.5）
A． ①； ②⑧④； ⑤
B． ①②； ③； ④⑤
C．①②； ③④； ⑤
D． ①； ②； ③④⑤發(fā)布：2024/12/27 13:0:1組卷：16引用：1難度：0.5
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