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A recent study of ancient and modern elephants has come up with the unexpected conclusion that the African elephant is divided into two distinct (不同的) species
The discovery was made by researchers at York and Harvard universities when they were examining the genetic relationship between the ancient woolly mammoth and mastodon to modern elephants—the Asian elephant, African forest elephant and African savanna elephant
Once they obtained DNA sequences (序列) from two fossils (化石)，mammoths and mastodons the team compared them with DNA from modern elephants. They found to their amazement that modern forest and savanna elephants are as distinct from each other as Asian elephants and mammoths.
The scientists used detailed genetic analysis to prove that the African savanna elephants and the African forest elephants have been distinct species for several million years. The divergence of the two species took place around the time of the divergence of Asian elephants and woolly mammoths. This result amazed all the scientists.
There has long been debate in the scientific community that the two might be separate species but this is the most convincing scientific evidence so far that they are indeed different species.
Previously, many naturalists believed that African savanna elephants and African forest elephants were two populations of the same species despite the elephants’ significant size differences. The savanna elephant has an average shoulder height of 3.5metres while the forest elephant has an average shoulder height of 2.5metres. The savanna elephant weighs between six and seven tons, roughly double the weight of the forest elephant. But the fact that they look so different does not necessarily mean they are different species. However, the proof lay in the analysis of the DNA.
Alfred Roca, assistant professor in the department of Animal Sciences at the University of Minois, said, “We now have to treat the forest and savanna elephants as two different units for conservation purpose. Since 1950 all African elephants have been conserved as one species. Now that we know the forest and savanna elephants are two very distinct animals, the forest elephant should become a bigger priority (优先)for conservation purpose .”
1.One of the fossils studied by the researchers is that of ________.
A. the Asian elephant B. the forest elephant
C. the savanna elephant D. the mastodon elephant
2.The underlined word “divergence” in paragraph 4means “________”
A. evolution B. exhibition C. separation D. examination
3.The researcher’s conclusion was based on a study of the African elephant’s ____________
A. DNA B. height C. weight D. population
4.What were Alfred Roca’s words mainly about?
A. The conversation of African elephants.
B. The purpose of studying African elephants
C. The way to divide African elephants into two units
D. The reason for the distinction of African elephants
5.Which of the following can be the best title for the passage?
A. Naturalist’s Belief about Elephants.
B. Amazing Experiment about Elephants
C. An Unexpected Finding about Elephants
D. A Long scientific Debate about Elephants
高二英语阅读理解中等难度题查看答案及解析
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A recent study of ancient and modern elephants has come up with the unexpected conclusion that the African elephant is divided into two distinct(不同的) species.
The discovery was made by researchers at York and Harvard Universities when they were examining the genetic relationship between the ancient woolly mammoth and mastodon to modern elephants — the Asian elephant, African forest elephant, and African savanna elephant.
Once they obtained DNA sequences(序列) from two fossils(化石), mammoths，and mastodons the team compared them with DNA from modern elephants. They found to their amazement that modern forest and savanna elephants are as distinct from each other as Asian elephants and mammoths.
The scientists used detailed genetic analysis to prove that the African savanna elephant and the African forest elephant have been distinct species for several million years. The divergence of the two species took place around the time of the divergence of Asian elephants and woolly mammoths. This result amazed all the scientists. There has long been debate in the scientific community that the two might be separate species, but this is the most convincing scientific evidence so far that they are indeed different species.
Previously, many naturalists believed that African savanna elephants and African forest elephants were two populations of the same species, despite the elephants’ significant size differences. The savanna elephant has an average shoulder height of 3.5 metres while the forest elephant has an average shoulder height of 2.5 metres. The savanna elephant weighs between six and seven tons, roughly double the weight of the forest elephant. But the fact that they look so different does not necessarily mean they are different species. However the proof lay in the analysis of the DNA.
Alfred Roca, assistant professor in the Department of Animal Sciences at the University of Illinois, said, “We now have to treat the forest and savanna elephants as two different units for conservation purposes. Since 1950，all African elephants have been conserved as one species. Now that we know the forest and savanna elephants are two very distinctive animals, the forest elephant should become a bigger priority(优先) for conservation purposes.”
1.One of the fossils studied by the researchers is that of _____.
A. the Asian elephant B. the forest elephant
C. the savanna elephant D. the mastodon elephant
2.The researchers’ conclusion was based on a study of the African elephant’s _____.
A. DNA B. height
C. weight D. population
3.What are Alfred Roca’s words mainly about?
A. The conservation of African elephants.
B. The purpose of studying African elephants.
C. The way to divide African elephants into two units.
D. The reason for the distinction of African elephants.
4.Which of the following can be the best title for the passage?
A. Naturalists’ Beliefs about Elephants
B. Amazing Experiments about Elephants
C. An Unexpected Finding about Elephants
D. A Long Scientific Debate about Elephants
高二英语阅读理解中等难度题查看答案及解析
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Languages have been coming and going for thousands of years, but in recent times there has been less coming and a lot more going. When the world was still populated by hunter-gatherers, small, tightly knit(联系) groups developed their own patterns of speech independent of each other. Some language experts believe that 10,000 years ago, when the world had just five to ten million people, they spoke perhaps 12,000 languages between them.
Soon afterwards, many of those people started settling down to become farmers, and their languages too became more settled and fewer in number. In recent centuries, trade, industrialization, the development of the nation-state and the spread of universal compulsory education, especially globalisation and better communications in the past few decades, all have caused many languages to disappear, and dominant languages such as English, Spanish and Chinese are increasingly taking over.
At present, the world has about 6,800 languages. The distribution of these languages is hugely uneven. The general rule is that mild zones have relatively few languages. Often spoken by many people while hot, wet zones have lots, often spoken by small numbers. Europe has only around 200 Languages: the Americas about 1,000, Africa 2,400; and Asia and the Pacific perhaps 3,200, of which Papua New Guinea alone accounts for well over 800. The median number(中位数) of speakers is a mere 6.000, which means that half the worlds languages are spoken by fewer people than that.
Already well over 400 of the total of 6,800 languages are close to extinction(消亡), with only a few elderly speakers left. Pick, at random, Busuu in Cameroon (eight remaining speakers), Chiapaneco in Mexico(150). Lipan Apache in the United States(two or three) or Wadjigu in Australia (one, with a question-mark): none of these seems to have much chance of survival.
1.What can we infer about languages in hunter-gatherer times?
A. They developed very fast. B. They were large in number.
C. They had similar patters. D. They were closely connected
2.Which of the following best explains "dominant" underlined in paragraph 2？
A. Complex. B. Advanced.
C. Powerful. D. Modern.
3.How many languages are spoken by less than 6, 000 people at present?
A. About 6,800 . B. About 3,400
C. About 2,400 D. About 1,200.
4.What is the main idea of the text?
A. New languages will be created.
B. Peoples lifestyles are reflected in languages.
C. Human development results in fewer languages.
D. Geography determines language evolution.
高二英语阅读理解困难题查看答案及解析
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Flying like a bird has been the dream of humans since ancient times. Last week a group of modern birdmen put their courage on their wings and challenged gravity in Hangzhou, Zhejiang Province.
“Yes, you can buy a ticket and fly to another city. But running with your own wings and feeling your feet ready to take off is totally different,” Dong Fang, said in an excited voice. He is one of 41 students from Hangzhou No. 14 Middle School to test their home-made aircrafts in the playground. Inspired by the International Bognor Birdman Competition in the UK, Ni Wangyue, a teacher in high school is holding a similar event. The Bognor Birdman competition started in 1971 in the England coastal city Bognor. People ran off the end of a pier (码头) with their own aircraft in an attempt to “fly” the farthest distance.
“From the very beginning , I
didn’t expect my students to create a real plane or break any records. I told them the competition is more for seeing how far your imagination can stretch,” Said Ni. He was surprised to see his students create 10 different aircrafts with all kinds of material available in the past month. Many students said that they learnt much more in the process of creating their planes than in ordinary classes.Jing Yuchen and his team named their plane “Weiming E”, which means an unknown goose. The 17-year-old boy deeply believes their goose of steel pipe and sailcloth will honour its name by successfully making it fly.
“Our work is much more imaginative than others. With several colourful balloons on its back and a pair of light plastic wings, it surely is the most eye-catching work, if not the best,” said Yu Liang, another student.
“Although most of those home-made aircrafts cannot really take the boys flying, the boys’ braveness and creativity in this project will encourage every one of them to fly high in the future,” Ni said.
1.The purpose of the competition is to ___________.
A. prepare to create more real planes.
B. let students break some records.
C. run off the end of a pier.
D. encourage braveness and creativity.
2.According to the passage, which of the following statements is NOT true?
A. There were 41 students taking part in the competition.
B. A similar kind of competition started in 1971.
C. The teacher didn’t expect his students could create 10 different aircrafts.
D. Most of those home-made aircrafts could take the boys flying.
3. By saying “you can buy a ticket and fly to another city”, the writer actually means ___________.
A. if you want to take part in the competition you have to buy a ticket.
B. people who take part in the competition have to fly to another city.
C. people can pay to get a chance to go to another place by air.
D. the students have to fly to another city in their home-made aircrafts.
4.Why did the teacher organize this activity?
A. He wanted to develop students’ imagination.
B. He wanted his students to have the feeling of flying.
C. He wanted his students to break records.
D. He wanted to increase his students’ grades.
高二英语阅读理解中等难度题查看答案及解析
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Every student has his own style of studying and it's up to you to use the available resources to be as effective and productive as possible.Here are some tips on how to teach yourself to study effectively.
●1.When determining the best approach,you need to assess your personality.Some people can read for hours while others can't sit still through more than one chapter.Find your pace,improve it and work around your strengths and weaknesses.It's up to you whether to join a study group or learn by yourself.
●Set a goal.2.It'll not only help you keep focused and stay on track but also help you organize your time and activities.
●Learn over time.3.If you don't know or understand the lesson from the start,you won't get it the night before your big test.It's best to study smaller loads of information repeated over a period of time.
●Set a realistic and reasonable schedule.4.Create a routine schedule for your studying time.Strictly follow this schedule so as to develop an effective studying session.
●Have time to rest.It's necessary to have enough time to rest in order to regain all the energy used up by the body from all the studying.5.Communicate with other people and participate in recreational activities to help you relax and refresh your mind.
A.Know yourself.
B.Have good study habits.
C.It's impossible to learn a lot of things in a short time.
D.Try to discover the type of reading that best suits you.
E.Allocate your time between studying and other activities.
F.Your mind won't be as sharp if you don't have ample sleep.
G.You need to determine what you want to achieve in a given subject.
高二英语七选五中等难度题查看答案及解析
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A recent study led by researchers from the National University of Singapore (NUS) has found a clear link between the color of a taxi and its accident rate. An analysis of 36 months of detailed taxi, driver and accident data from two fleets of yellow and blue taxis in Singapore suggested that yellow taxis have fewer accidents than blue taxis. The higher visibility (能见度） of yellow makes it less difficult for drivers to avoid getting into accidents with yellow taxis, leading to a lower accident rate.
The study was led by Prof Ho. To test whether there was a relationship between the color of a taxi and the number of accidents the taxi had, the research team analysed data collected by the largest taxi company in Singapore. The researchers found that yellow taxis have about 6. 1 fewer accidents per 1,000 taxis per month.
They also studied the economic effect of changing the color of the entire fleet of taxis to yellow. The Singapore taxi company involved in the study owns about 16,700 taxis in a ratio (比例) of one yellow to three blue taxis. If a commercial decision is made to switch from blue to yellow taxis, 76. 6 fewer accidents will occur per month or 917 fewer accidents per year.
Assuming an average repair cost of $1,000 per car and a downtime of six days, the color of all taxis to yellow could produce an annual saving of $2 million.
“We are eager to continue to validate (证实) the findings of our study by looking at the use of yellow in other types of public transport, such as school buses. For example, we hope to compare the accident rates of yellow school buses against those of other colors to find out if yellow is indeed a safer color for school buses. Besides, we’ re also interested to look at private-hire vehicles and do a comparison of the accident rates of vehicles that are of different colors explained Prof Ho.
1.Why do yellow taxis result in fewer accidents?
A. Because yellow signals a warning of danger.
B. Because yellow can be seen more easily.
C. Because drivers tend to he more careful in yellow taxis.
D. Because people act more quickly in yellow surroundings.
2.What’ s Prof Ho’s study based on?
A. Physical risks taxi passengers experience.
B. The economic effect of changing taxi color.
C. Personal reports from taxi drivers worldwide.
D. Data from Singapore's largest taxi company.
3.What do Prof Ho’s words in the last paragraph suggest?
A. School buses should be painted yellow.
B. Their findings are worth popularizing.
C. Their study will be furthered.
D. Yellow should be widely used in public transport,
4.What can be the best title for the text?
A. Safer to ride in yellow taxis B. Caution: yellow taxis ahead
C. Why are yellow Taxis preferred? D. How can colors help prevent accidents?
高二英语阅读理解困难题查看答案及解析
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Hillcrest Museum
Enjoy an experience of digging up the past. Handle pieces of ancient tools and other objects from many countries. Learn to date them and see what they tell us about how people lived then. School groups should book in advance.
Open daily July 1 until Labour Day weekend.
Admission fees are $5.00 per adult, $3.00 per student; children under 5 are free.
Red House
Travel back to the time of the novelist Charlotte Bronte and find out about her friends and local connections. Discover the comforts and discomforts of the 1830s country home where Charlotte sometimes stayed as a guest of Joshua Taylor's family and got ideas for her novel Shirley.
Admission by guided tour only at 11 am. Last admission 45 minutes before closing.
Admission fees are $8.00 per adult, $4.00 per child.
Castle Museum
The castle was built looking down on the valley of the River Dean. It is now a museum, where you can learn how the valley has changed over millions of years. There is a collection of interesting rocks found in the area, and pictures showing how the valley probably looked in prehistoric times.
Hours & Admission
Tuesday-Saturday: 10 am-4:30 pm
Adults: $1
Children: 50 cents
1.How much should a couple with their 4-year-old kid pay to visit Hillcrest Museum?
A.$10.00. B.$13.00.
C.$15.00. D.$20.00.
2.Which museum can help you know about Charlotte Bronte?
A.Hillcrest Museum. B.Red House.
C.Castle Museum. D.Shandy Hall.
3.What can you find in Castle Museum?
A.A variety of rocks.
B.World-famous pictures.
C.A large beautiful garden.
D.Old tools from many countries.
高二英语阅读理解简单题查看答案及解析
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A recent study has shown that eating a small amount of dark chocolate every day could be good for your health. Scientists have found that a regular 2 ounces can help lower blood pressure and reduce the risk of having a heart attack or stroke（中风）without any weight gain. But take care before you reach for a large bar. The effects are canceled out if more than 30 calories are taken into your body each day, the researchers warn.
It’s already known that a chemical called polyphenol（多酚）, found in chocolate, can help reduce blood pressure, and blood pressure lowered in this way can reduce the risk of death from a stroke by 8 percent and from a heart attack by 5 percent, scientists declare. And it can also reduce the risk or death in general by 4 percent.
A daily diet with a little chocolate has the same effect with some special diets designed to lower blood pressure, according to one researcher. “Although all the degree of the blood pressure reduction is small, the effects are quite obvious,” the researchers said.
However, Sara Stanner, a nutritionist at the British Heart Foundation, is quite cautious. “This study suggests that small quantities of small chocolate might have good effects on blood pressure. However, it is important to remember that chocolate is also high in fat and calories. So eating much is not good for your heart.” “Polyphenols are also found in fruits and vegetables, which can be taken in without the risks associated with overintake,” she added.
But the German study shows that the fat content does not cancel out the good effects—at least where small amounts are concerned.
1.How is Paragraph 2 developed?
A. By making comparisons. B. By listing figures.
C. By analyzing causes. D. By giving examples.
2.What health benefits does dark chocolate have?
A. It lowers blood pressure heavily.
B. It may prevent heart attacks in a way.
C. It’s useful for controlling one’s weight.
D. It helps people strengthen their body.
3.What do Sara Stanner’s words suggest?
A. Eating chocolate has no health benefits.
B. Dark chocolate is not so nutritious as expected.
C. The findings of scientist’s study are not scientific.
D. Eating fruits and vegetables may be a better choice.
4.What will be discussed in the following passage?
A. Some details of the German study.
B. Benefits of fruits and vegetables.
C. Harm of overeating dark chocolate.
D. The proper amount of dark chocolate taken in.
高二英语阅读理解中等难度题查看答案及解析
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The country has sent up three manned spacecraft, the most recent ___ at the end of last March.
A.has been launched B.being launched C.having been launched D.to be launched
高二英语单项填空中等难度题查看答案及解析
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In the countries of South and Southeast Asia, the elephant has been an important part of the culture, economy and religion for centuries. And nowhere more so than in Thailand. Unlike its African cousin, the Asian elephant is easily domesticated（驯化）. The rare so-called white elephants have actually lent the power of royalty (皇室)to its rulers，and until the 1920s the national flag was a white elephant on a red background. To the early Western visitors, the country's romantic name was“ Land of the White Elephant".
Today, however, the story is very different. Out of work and out of land, the Thai elephant struggles for survival in a nation that no longer needs it. The elephant has found itself more or less deserted by previous owners who have moved on to a different economic world and a society in the western part. And while the elephant's problems began many years ago, now it has a very low national advantage.
How does the national symbol turn into ignored animals? It is a story of worse environment and the changing lives of the Thais themselves. According to Richard Lair, Thailand's expert on the Asian elephant and author of the report Gone Astray, at the turn of the last century, there may well have been as many as 100,000 national elephants in the country.
In the north of Thailand alone, it was estimated（估计）that more than 20,000 elephants were employed in transport, 1,000 of them alone on the road between the cities of Chiang Mai and Chiang Saen.
This was at a time when 90 percent of Thailand was still forest---a habitat that not only supported the animals but also made them necessary to carry goods and people. Nothing ploughs through thick forest better than lots of sure-footed elephants.
By 1950 the elephant population had dropped, but still to the number of 13, 397. However, today there are probably no more than 3,800, with another l,350 wandering free in the national parks. But now, Thailand's forest covers only 20 percent of the land. This deforestation（采伐森林）is the central point of the elephant's difficult situation, for it has effectively put the animals out of work. This century, as the road network grew, the elephant's role as a beast of burden decreased.
1.What can we know about African elephants from the passage?
A. It is of little value to domesticate them.
B. It is hard to domesticate them.
C. They are living a better life than Asian elephants.
D. Their fate is quite similar to that of Asian elephants.
2.Thailand was once called "Land of the White Elephant" because ________.
A. white elephant was a national symbol until the 1920s
B. white elephant is rarely seen and thus very special
C. white elephant has helped kings to gain the ruling authority
D. this name was so romantic that it was popular among visitors
3.Why is the Thai elephant "out of work", according to the author?
A. Because there are too many elephants but too few jobs.
B. Because the elephants can't do labor work any longer.
C. Because the government pays little attention to the problem.
D. Because the elephants are no longer useful to their owners.
4.The passage is most probably from ________.
A. a travel guide
B. a history book
C. a popular science magazine
D. an official announcement
高二英语阅读理解中等难度题查看答案及解析
didn’t expect my students to create a real plane or break any records. I told them the competition is more for seeing how far your imagination can stretch,” Said Ni. He was surprised to see his students create 10 different aircrafts with all kinds of material available in the past month. Many students said that they learnt much more in the process of creating their planes than in ordinary classes.