City trees grow faster and die younger than trees in rural forestry, a new study finds. Over their lifetimes,then, urban trees will likely absorb less CO2 from the air thah forest trees.
As we all know, the earth would be freezing or burning hot without C02. However, CO2 is a greenhouse gas, meaning it traps energy from the sun as/heat. That makes temperatures near the ground rise. Human activities, especially the widespread burning-of fossil(化石）fuels，have been sending extra greenhouse gases into the air. This has led to a rise in average temperatures across the globe.
Studies had shown forests readily absorb C02，but there hadn’t been much data on whether city trees grow， die and absorb CO2 at the same rate as forest trees do. So some researchers decided to find out.
To figure out how quickly trees were growing, researchers tracked their diameters (the width of their trunks) between 2005 and 2014. A tree’s diameter increases as it grows, just as a person’s waist size increases as they gain weight. About half the weight of a tree is carbon, research has shown. Most of the rest is water. Over the nine years’ tracking, the researchers found city trees absorbed four times as much carbon from the air as forest trees. However, they were twice as likely to die. So over the lifetime of each type of tree, forest trees actually absorbed more C02.
City trees grew faster because they had less competition for light from their neighbors. In a forest，trees tend to grow close together，shading their neighbors. Street trees also benefit from higher levels of nitrogen (氮）in rainwater. Nitrogen helps plants grow. Waste gases from gas-burning cars also contain nitrogen, thus enriching city air with nitrogen. Later, rainwater may wash much of it to the ground. Some street trees may also have better access to water than trees in the country because the underground water pipes can leak.
1.What can he known about CO2 from paragraph 2?
A.It is one of the side effects of greenhouses.
B.It greatly accelerates the process of global warming.
C.It results from the widespread burning of fossil fuels.
D.It prevents the earth from becoming unsuitable to live on.
2.Why did researchers track the diameters of trees?
A.To know about their growth rates.
B.To find out how much they weigh.
C.To check whether they were healthy.
D.To assess the carbon amounts in them.
3.What advantage do city trees have over forest trees?
A.They are more likely to access growth promoters.
B.They can enjoy more water coming from the air.
C.They can enjoy more shade from neighbors.
D.They are better at competing for light.
4.What will probably be talked about if the passage is continued?
A.How urban trees can live longer.
B.Why city living makes trees die young.
C.How trees respond to dry soil conditions.
D.Why faster-growing trees absorb more C02.
高三英语阅读理解困难题
City trees grow faster and die younger than trees in rural forestry, a new study finds. Over their lifetimes,then, urban trees will likely absorb less CO2 from the air thah forest trees.
As we all know, the earth would be freezing or burning hot without C02. However, CO2 is a greenhouse gas, meaning it traps energy from the sun as/heat. That makes temperatures near the ground rise. Human activities, especially the widespread burning-of fossil(化石）fuels，have been sending extra greenhouse gases into the air. This has led to a rise in average temperatures across the globe.
Studies had shown forests readily absorb C02，but there hadn’t been much data on whether city trees grow， die and absorb CO2 at the same rate as forest trees do. So some researchers decided to find out.
To figure out how quickly trees were growing, researchers tracked their diameters (the width of their trunks) between 2005 and 2014. A tree’s diameter increases as it grows, just as a person’s waist size increases as they gain weight. About half the weight of a tree is carbon, research has shown. Most of the rest is water. Over the nine years’ tracking, the researchers found city trees absorbed four times as much carbon from the air as forest trees. However, they were twice as likely to die. So over the lifetime of each type of tree, forest trees actually absorbed more C02.
City trees grew faster because they had less competition for light from their neighbors. In a forest，trees tend to grow close together，shading their neighbors. Street trees also benefit from higher levels of nitrogen (氮）in rainwater. Nitrogen helps plants grow. Waste gases from gas-burning cars also contain nitrogen, thus enriching city air with nitrogen. Later, rainwater may wash much of it to the ground. Some street trees may also have better access to water than trees in the country because the underground water pipes can leak.
1.What can he known about CO2 from paragraph 2?
A.It is one of the side effects of greenhouses.
B.It greatly accelerates the process of global warming.
C.It results from the widespread burning of fossil fuels.
D.It prevents the earth from becoming unsuitable to live on.
2.Why did researchers track the diameters of trees?
A.To know about their growth rates.
B.To find out how much they weigh.
C.To check whether they were healthy.
D.To assess the carbon amounts in them.
3.What advantage do city trees have over forest trees?
A.They are more likely to access growth promoters.
B.They can enjoy more water coming from the air.
C.They can enjoy more shade from neighbors.
D.They are better at competing for light.
4.What will probably be talked about if the passage is continued?
A.How urban trees can live longer.
B.Why city living makes trees die young.
C.How trees respond to dry soil conditions.
D.Why faster-growing trees absorb more C02.
高三英语阅读理解困难题查看答案及解析
Special trees that grow faster, fight pollution, produce better wood, and even sense chemical attacks are being planted by scientists in the US．
When 40 per cent of Hawaii's US$14 million-a-year papaya （木瓜）industry was destroyed by a virus five years ago, work began on creating genetically engineered（转基因的）trees．
Researchers successfully introduced seeds that were designed to resist the virus．Since then, more and more people have been testing genetically engineered trees．Some researchers put special bacteria into trees to help them grow faster and produce better wood．Others are trying to create trees that can clean polluted soil．Meanwhile fruit farmers are looking for trees that are strong enough to resist worms, and paper companies want trees that produce more wood and therefore more paper．
The Pentagon （五角大楼） even gave the researchers US$500,000 this year after they developed a pine tree that changes its colours if it senses a chemical attack．So far, the poplar, eucalyptus （杨树与桉树）, apple and coffee trees are among those being engineered．All this can be done today because we have a better understanding of tree genomes （基因组）．
However, some people fear that the genetically engineered trees will cause dangerous results．They are worried that the new trees will breed with natural species and change the balance of the forest environment．
“It could be destructive,” said Jim Diamond, an environmentalist. “Trees are what is left of our natural environment and home to many endangered species.”
But researchers insist that science could give nature a fighting chance against both natural and man-made dangers．They hope to answer the critics by stopping the new trees from breeding, so their effect on the environment can be controlled．
63．Which kind of tree is not the ones that scientists are planting in the US?
A．Trees that worms can't hurt．
B．Genetically engineered trees．
C．Trees that can resist wind better．
D．Trees that can protect themselves at a chemical attack．
64．What caused the American scientists to work on special trees?
A．Tree genomes are mapped out so scientists know how to improve trees．
B．Great numbers of trees have been lost due to attacks by viruses．
C．Researchers successfully introduced seeds designed to resist the virus．
D．They think science could give nature a fighting chance against both natural and man-made dangers．
65．Which of the following was probably the first kind of trees being engineered?
A．Papaya． B．Pine． C．Apple． D．Poplar．
66．Why did critics think engineered trees dangerous? Because ________．
A．these trees can destroy the balance of nature
B．everything except trees has been genetically engineered
C．trees are home to many endangered species
D．these trees may affect normal trees
高三英语阅读理解简单题查看答案及解析
Special trees that grow faster, fight pollution, produce better wood, and even sense chemical attacks are being planted by scientists in the US．
When 40 per cent of Hawaii's US$14 million-a-year papaya （木瓜）industry was destroyed by a virus five years ago, work began on creating genetically engineered（转基因的）trees．
Researchers successfully introduced seeds that were designed to resist the virus．Since then, more and more people have been testing genetically engineered trees．Some researchers put special bacteria into trees to help them grow faster and produce better wood．Others are trying to create trees that can clean polluted soil．Meanwhile fruit farmers are looking for trees that are strong enough to resist worms, and paper companies want trees that produce more wood and therefore more paper．
The Pentagon （五角大楼） even gave the researchers US$500,000 this year after they developed a pine tree that changes its colours if it senses a chemical attack．So far, the poplar, eucalyptus （杨树与桉树）, apple and coffee trees are among those being engineered．All this can be done today because we have a better understanding of tree genomes （基因组）．
However, some people fear that the genetically engineered trees will cause dangerous results．They are worried that the new trees will breed with natural species and change the balance of the forest environment．
“It could be destructive,” said Jim Diamond, an environmentalist. “Trees are what is left of our natural environment and home to many endangered species.”
But researchers insist that science could give nature a fighting chance against both natural and man-made dangers．They hope to answer the critics by stopping the new trees from breeding, so their effect on the environment can be controlled．
1.Which kind of tree is not the ones that scientists are planting in the US?
A．Trees that worms can't hurt．
B．Genetically engineered trees．
C．Trees that can resist wind better．
D．Trees that can protect themselves at a chemical attack．
2.What caused the American scientists to work on special trees?
A．Tree genomes are mapped out so scientists know how to improve trees．
B．Great numbers of trees have been lost due to attacks by viruses．
C．Researchers successfully introduced seeds designed to resist the virus．
D．They think science could give nature a fighting chance against both natural and man-made dangers．
3.Which of the following was probably the first kind of trees being engineered?
A．Papaya． B．Pine． C．Apple． D．Poplar．
4.Why did critics think engineered trees dangerous? Because ________．
A．these trees can destroy the balance of nature
B．everything except trees has been genetically engineered
C．trees are home to many endangered species
D．these trees may affect normal trees
高三英语阅读理解中等难度题查看答案及解析
Special trees that grow faster, fight pollution, produce better wood, and even sense chemical attacks are being planted by scientists in the US．
When 40 per cent of Hawaii's US$14 million-a-year papaya （木瓜）industry was destroyed by a virus five years ago, work began on creating genetically engineered（转基因的）trees．
Researchers successfully introduced seeds that were designed to resist the virus．Since then, more and more people have been testing genetically engineered trees．Some researchers put special bacteria into trees to help them grow faster and produce better wood．Others are trying to create trees that can clean polluted soil．Meanwhile fruit farmers are looking for trees that are strong enough to resist worms, and paper companies want trees that produce more wood and therefore more paper．
The Pentagon （五角大楼） even gave the researchers US$500,000 this year after they developed a pine tree that changes its colours if it senses a chemical attack．So far, the poplar, eucalyptus （杨树与桉树）, apple and coffee trees are among those being engineered．All this can be done today because we have a better understanding of tree genomes （基因组）．
However, some people fear that the genetically engineered trees will cause dangerous results．They are worried that the new trees will breed with natural species and change the balance of the forest environment．
“It could be destructive,” said Jim Diamond, an environmentalist. “Trees are what is left of our natural environment and home to many endangered species.”
But researchers insist that science could give nature a fighting chance against both natural and man-made dangers．They hope to answer the critics by stopping the new trees from breeding, so their effect on the environment can be controlled．
1.Which kind of tree is not the ones that scientists are planting in the US?
A．Trees that worms can't hurt．
B．Genetically engineered trees．
C．Trees that can resist wind better．
D．Trees that can protect themselves at a chemical attack．
2.What caused the American scientists to work on special trees?
A．Tree genomes are mapped out so scientists know how to improve trees．
B．Great numbers of trees have been lost due to attacks by viruses．
C．Researchers successfully introduced seeds designed to resist the virus．
D．They think science could give nature a fighting chance against both natural and man-made dangers．
3.Which of the following was probably the first kind of trees being engineered?
A．Papaya． B．Pine． C．Apple． D．Poplar．
4.Why did critics think engineered trees dangerous? Because ________．
A．these trees can destroy the balance of nature
B．everything except trees has been genetically engineered
C．trees are home to many endangered species
D．these trees may affect normal trees
高三英语阅读理解中等难度题查看答案及解析
Growing up in rural Malawi, Africa, William Kamkwamba’s life was filled with ancient way and mystery. His family was _________ and they lived in a small house without electricity. At night, they went to bed early because the kerosene（煤油）to light the lamps was _________.
A terrible drought in 2000 left many Malawians _________. Security was having sacks of corn and not having them was _________. He still wanted to learn and when he was _________ from school by his inability to pay the _________, he found the free library. There he read a book called Using Energy, which _________ him in science and gave him an idea that _________changed his future. In the book, William found a picture of a windmill, and a brief _________ of how it could be used to generate __________ from wind. He realized that if he could __________ a windmill, his village people could live a far better ________.
The next year witnessed William’s __________ and determination. He began to collect any material __________ --pieces of wood, broken bicycles--and started to build a windmill. He __________ many challenges and failures. Finally, at the age of 14, William __________ his first one. Seeing electric __________ coming from William’s house, the village people came running. He had found a way to __________ the wind.
William Kamkwamba has made the world realize that even the starving kids in Malawi have much to __________. He struggle with his dreams and __________ hardships in his life, yet he always worked hard, and never gave up.
1.A.poor B.unique C.extended D.supportive
2.A.available B.costly C.adequate D.free
3.A.homeless B.clumsy C.unconscious D.hungry
4.A.dignity B.liberty C.death D.shame
5.A.dismissed B.blocked C.discouraged D.suspended
6.A.insurance B.treatment C.wages D.fees
7.A.involved B.established C.proved D.trained
8.A.deliberately B.consistently C.significantly D.temporarily
9.A.application B.description C.assumption D.decoration
10.A.wave B.energy C.electricity D.heat
11.A.design B.replace C.upgrade D.construct
12.A.life B.survival C.scene D.dream
13.A.consideration B.qualification C.reputation D.ambition
14.A.useful B.wonderful C.valuable D.portable
15.A.refused B.braved C.detected D.indicated
16.A.donated B.restored C.completed D.imported
17.A.current B.light C.shock D.charge
18.A.blow B.measure C.estimate D.capture
19.A.offer B.recommend C.protest D.advocate
20.A.ran into B.figured out C.went through D.brought in
高三英语完形填空中等难度题查看答案及解析
The universe is expanding faster than it used to, meaning it’s about a billion years younger than we thought, a new study by a Nobel Prize winner says.
At issue is a number called the Hubble constant, a calculation for how fast the universe is expanding. Some scientists call it the most important number in cosmology, the study of the origin and development of the universe.
Using NASAS Hubble Space Telescope, lohns Hopkings University astronomer Adam Riess concluded in this week’s Astrophysical Journal that the figure is 9% higher than the previous calculation, which was based on studying leftovers from the Big Bang.
The trouble is， Riess and others think both calculations are correct. Confused? That’s OK, so are the experts. They find the conflict so confusing that they are talking about coming up with “new physics”, incorporating (合作) perhaps some yet-to-be-discovered particle or other cosmic (宇宙) “fudge factors” like dark energy or dark matter
“Its looking more and more like were going to need something new to explain this,” said Reiss, who won the 2011 Nobel in physics.
NASA astrophysicist John Mather, another Nobel winner, said this leaves two obvious options, “1. We’re making mistakes we can’t find yet. 2. Nature has something we can’t find yet.”
Even with the discovery, life continues on Earth the way it always has. But to astrophysicists trying to get a handle on our place in this expanding universe, this is a cosmic concern. In fact, the universe is really mystical (神秘的). Scientists have done lots of study about it but there is still much they haven’t discovered.
1.What is the finding of the new study?
A.The earth is younger than expected.
B.Many universal problems are rising.
C.The universe is growing faster than before.
D.The finding is based on past scientists’ calculations.
2.What does the underlined word “it” refer to in Paragraph 2?
A.The Hubble constant. B.The faster expanding universe.
C.The development of the universe. D.The scientific research on the universe.
3.How do the experts respond to the conflict of the finding in Paragraph 4?
A.They want to raise a new theory.
B.They want to explore dark matter.
C.They want to further calculate the finding.
D.They want to mix together both calculations.
4.What can we infer from John Mather’s words?
A.We cannot find anything useful.
B.Astronomers are making many mistakes.
C.We need to learn about the universe.
D.We cannot find something new from nature.
高三英语阅读理解困难题查看答案及解析
Norm lives in a rural area some distance from the nearest city and a much longer distance from the nearest big hospital so when his wife got cancer several years ago Norm was faced with a four and a half hour drive to where she could be treated．That meant lots of expense for meals，fuel，hotels and so on but in the end the cancer took his wife anyway．
Norm was obviously very stricken by his wife’s passing but he was also very angry because he realized that other people were facing the same sorts of hardships．He wanted to do something but he didn’t want to give money to the charities(慈善机构)that support cancer research because he didn’t know how much of it would actually get to the researchers．What he did was start to hold parties．
About every three weeks on Saturday evenings there is a party in Norm’s garden．Neighbours，friends and relatives come and bring snacks and drinks；many bring instruments，there is music and lancing and at some point during the evening Norm tells about a family he has found who are having difficulties meeting the cost of supporting a cancer patient undergoing treatment far from home．Then a honey-pail is passed around and the money collected，every cent of it，goes directly to that family．
Norm’s passion to help the families of other cancer patients was born out of his grief but Norm’s personal loss has resulted in an act of kindness that honours the memory of the wife he has lost．He makes the world a better place．
1.What do we know about Norm’s wife?
A．She died for lack of money．
B．She worked in a distant hospital．
C．She lost the battle against cancer．
D．She took good care of her family．
2.How does Norm help others?
A．By giving money to charities．
B．By supporting cancer researchers．
C．By telling stories to his friends．
D．By raising money through parties．
3.At Norm’s party，the“honey-pail”is used to contain______．
A．snacks B．drinks C．honey D．money
4.Through what he does，Norm probably wants to____________．
A．remember his wife B．hide his anger
C．regain his personal loss D．change the world
高三英语阅读理解中等难度题查看答案及解析
This place was darker than I expected, and, in spite of the rain, dirtier. Used to the life of rural Puerto Rico(波多黎各), I had to adjust to the similarly arranged, aggressive two-dimensionality of New York. Everywhere I looked, my eyes met gray and brown straight-edged buildings with sharp corners and deep shadows. Every few blocks there was a cement(水泥) playground surrounded by chain-link fence.
A girl came out of the building next door, a jump rope in her hand, and she hopped over. “Are you Hispanic?” she asked. “No, I’m Puerto Rican.” “Same thing. Puerto Rican, Hispanic. That’s what we are here.” She skipped a tight circle, stopped abruptly, and shoved the rope in my direction. “Want a turn?”
“Sure.” I hopped on one leg, then the other. “So, if you’re Puerto Rican, they call you Hispanic?”
“Yeah. Anybody who speaks Spanish.”
I jumped a circle, as she had done, but faster. “You mean, if you speak Spanish, you’re Hispanic?”
“Well, yeah. No . . . I mean your parents have to be Puerto Rican or Cuban or something.”
“Okay, your parents are Cuban, let’s say, and you’re born here, but you don’t speak Spanish. Are you Hispanic?”
“I guess so,” she finally said. “It has to do with being from a Spanish country. I mean, you or your parents, like, even if you don’t speak Spanish, you’re Hispanic, you know?” She looked at me uncertainly. But I didn’t know. I’d always been Puerto Rican, and it hadn’t occurred to me that in New York I’d be someone else.
Later, I asked. “Are we Hispanics, Mami?” “Yes, because we speak Spanish.” “But a girl said you don’t have to speak the language to be Hispanic.” “What girl? Where did you meet a girl?” “Outside. She lives in the next building.” “Who said you could go out to the sidewalk? This isn't Puerto Rico. Something could happen to you.”
I listened to Mami’s lecture with depressed eyes and the necessary respect. But inside, I quaked. Two days in New York, and I’d already become someone else. It wasn’t hard to imagine that greater dangers lay ahead.
1.The first paragraph suggests that the author experienced New York as .
A. mysterious and unknowable
B. regular and depressing
C. orderly and appealing
D. impressive and dangerous
2.For the author, being considered Hispanic represents .
A. a restriction to be overcome
B. an opportunity for self-redefinition
C. the loss of her former identity
D. an unavoidable result of movement to a new place
3.The mother refers to “Puerto Rico” in order to impress upon the author that .
A. she should not miss her birthplace
B. New Yorkers may not like newcomers
C. different rules apply to life in New York
D. life was more restricted in Puerto Rico
4.The author’s mood can best be described as
A. angry and confused B. fearful and uncertain
C. excited but lonely D. worried and resistant
高三英语阅读理解中等难度题查看答案及解析
Atlanta was a Greek princess. She was very beautiful and could run faster than 31 man in Greece. But she was not allowed to run in the Olympic Games. She was 32 angry that she said to her father she would not marry anyone who could not run faster than her. Her father said she must marry and asked her 33 she wanted to marry a king or prince. But Atlanta replied, “I will only be married to a man who can run faster than me. When a man says he wants to marry me, I will run 34 him. If he cannot run as fast as me, he 35 (kill). No one will be pardoned.”
Many kings and princes wanted to marry Atlanta but when they heard of her rules, some of them 36 (sad) went home. Other men stayed to run the race. There was a man called Hippomenes who was amazed when he heard of Atlanta’s rules. “Why are these men so 37 (fool)? Why will they let 38 be killed because they cannot run as fast as this princess?” Then when he saw Atlanta come out of her house 39 (run), Hippomenes changed his mind. “I 40 marry Atlanta — or die!” he said.
高三英语填空题简单题查看答案及解析
Children in rural areas of Cambodia often suffer from or even die of preventable illnesses because there is not any soap available.
In 2014，Samir Lakhani，an American college student，saw the issue while volunteering in a Cambodian village.“I remember quite vividly a mother bathing her newborn baby with laundry powder，which is so harmful to the skin，”said Lakhani.“It’s difficult for rural Cambodians to access soap.First is affordability.If you earn only$1.50 every day，you won’t spend $1 on a bar of soap.Then comes access.The demand is so low that local shops don’t stock soap.The last reason，because many Cambodians don’t really understand where diseases come from，they don’t know how to prevent them，including using soap.”
After figuring out a solution to the problem:the barely-used soap in hotels，Lakhani started asking hotels to donate leftover soap.“They were all eager to help，”he explained.
Lakhani registered Eco-Soap Bank shortly afterwards.Soon，he received enough funds to hire disadvantaged Cambodian women to collect and reproduce the used soap.
Today，the organization has four recycling centers across the country，providing jobs to 35 local women.And so far，some 174，000 bars of soap have been donated，about 24，000 pounds of soap has been recycled，and hygiene(卫生)has been improved for about 661，000 people.“We are killing three birds with one stone，”Lakhani said.
When it comes to the future of Eco-Soap Bank，Lakhani said，“We’ve just scratched the surface.Lack of hygiene is not something unique to Cambodia.The demand for improved hygiene in the developing world is huge，and much remains to be done.We’re looking at seven countries to expand to in the near future.”
1.Which of the following is not mentioned as the reason why rural Cambodians don’t use soap?
A. Poverty. B. Inaccessibility. C. Unawareness. D. Tradition.
2.What does the underlined part“killing three birds”in Paragraph 5 refer to?
A. Saving soap，curing diseases and providing education.
B. Stopping pollution，proving jobs and inspiring donation.
C. Reducing waste，providing employment and improving health.
D. Recycling waste，helping charity and improving community hygiene.
3.What can we infer about Eco-Soap Bank?
A. It won’t be long before it expands to the whole world.
B. There’s little it can do without other countries’assistance.
C. It will make greater contributions to the developing world.
D. It will soon settle the problem of poor hygiene in Cambodia.
4.What does the text mainly talk about?
A. Eco-Soap Bank helps improve hygiene.
B. Cambodian women have a bright future.
C. A US young man calls for helping poor countries.
D. Lack of hygiene remains a serious problem in the world.
高三英语阅读理解中等难度题查看答案及解析