Strange ice rings in Siberia’s Lake Baikal have puzzled scientists for decades, but now the mystery apparently has been solved. The answer: the rings are caused by warm, circular currents of water under the ice, called eddies (漩涡).
The eddies’ strong currents melt the ice at the edge, but weaker ones keep the center frozen. “Results of our field surveys show that there are warm eddies that circulate in a clockwise (顺时针的) direction under the ice cover,” said Alexei Kouraev, a hydrologist at the University of Toulouse, in a NASA statement. “In the eddy center, the ice does not melt — even though the water is warm — because the currents are weak,” he said. “But on the eddy boundary, the currents are stronger, and warmer water leads to rapid melting.”
During field work, Kouraev and his colleagues drilled holes near ice rings and set sensors capable of measuring the temperature and salinity (盐浓度) of the water to a depth of 700 feet. They found that the water in the eddies was 2 to 4 ℉ warmer than the surrounding water.
Most of the rings appear in March or April and have a width of about 3 to 4 miles — too big to recognize from the ground but easily seen from satellites above. Some rings were ephemeral while others lasted for weeks or even months.
Lake Baikal is the world’s largest and deepest freshwater lake, according to Gizmodo. It’s home to many varieties of fish not seen anywhere else in the world, and even a population of freshwater seals.
Researchers are still investigating what causes Baikal’s eddies but think it’s likely because of wind patterns, rivers that flow into the lake and the shape of the lake’s coastline and bottom.
1.Which word can best replace the underlined word “ephemeral” in paragraph 4?
A.Steady. B.Current.
C.Fundamental. D.Temporary.
2.Why is the ice in the center of ice rings frozen while that at the edge is melted?
A.Because the center of ice rings is 2 to 4℉ warmer than the edge.
B.Because the currents in the center are less powerful.
C.Because it is too wide to be recognized or melted.
D.Because water in the center circulates in a clockwise direction.
3.Which of the following statements about Lake Baikal’s eddies is TRUE?
A.They are caused by hot and circular currents under the ice.
B.The ice in the center of Lake Baikal’s eddies melts faster than that of the edge.
C.Researchers are uncertain about the exact reason of the eddies’ existence.
D.Lake Beikal’s eddies can only be measured at the depth of 700 feet.
4.What maybe the best title for the passage?
A.What’s causing the giant ice rings in Siberia?
B.The mystery of the eddies' in the Lake Baikal uncovered.
C.The largest and deepest freshwater lake — Lake Baikal.
D.Why does the edge of an ice ring melt faster?
高三英语阅读理解中等难度题
Strange ice rings in Siberia’s Lake Baikal have puzzled scientists for decades, but now the mystery apparently has been solved. The answer: the rings are caused by warm, circular currents of water under the ice, called eddies (漩涡).
The eddies’ strong currents melt the ice at the edge, but weaker ones keep the center frozen. “Results of our field surveys show that there are warm eddies that circulate in a clockwise (顺时针的) direction under the ice cover,” said Alexei Kouraev, a hydrologist at the University of Toulouse, in a NASA statement. “In the eddy center, the ice does not melt — even though the water is warm — because the currents are weak,” he said. “But on the eddy boundary, the currents are stronger, and warmer water leads to rapid melting.”
During field work, Kouraev and his colleagues drilled holes near ice rings and set sensors capable of measuring the temperature and salinity (盐浓度) of the water to a depth of 700 feet. They found that the water in the eddies was 2 to 4 ℉ warmer than the surrounding water.
Most of the rings appear in March or April and have a width of about 3 to 4 miles — too big to recognize from the ground but easily seen from satellites above. Some rings were ephemeral while others lasted for weeks or even months.
Lake Baikal is the world’s largest and deepest freshwater lake, according to Gizmodo. It’s home to many varieties of fish not seen anywhere else in the world, and even a population of freshwater seals.
Researchers are still investigating what causes Baikal’s eddies but think it’s likely because of wind patterns, rivers that flow into the lake and the shape of the lake’s coastline and bottom.
1.Which word can best replace the underlined word “ephemeral” in paragraph 4?
A.Steady. B.Current.
C.Fundamental. D.Temporary.
2.Why is the ice in the center of ice rings frozen while that at the edge is melted?
A.Because the center of ice rings is 2 to 4℉ warmer than the edge.
B.Because the currents in the center are less powerful.
C.Because it is too wide to be recognized or melted.
D.Because water in the center circulates in a clockwise direction.
3.Which of the following statements about Lake Baikal’s eddies is TRUE?
A.They are caused by hot and circular currents under the ice.
B.The ice in the center of Lake Baikal’s eddies melts faster than that of the edge.
C.Researchers are uncertain about the exact reason of the eddies’ existence.
D.Lake Beikal’s eddies can only be measured at the depth of 700 feet.
4.What maybe the best title for the passage?
A.What’s causing the giant ice rings in Siberia?
B.The mystery of the eddies' in the Lake Baikal uncovered.
C.The largest and deepest freshwater lake — Lake Baikal.
D.Why does the edge of an ice ring melt faster?
高三英语阅读理解中等难度题查看答案及解析
Many of us know about Russia’s Lake Baikal from our textbooks, or by listening to Chinese singer Li Jian’s hit song, Lie Baikal. But over the past decade, the world’s deepest freshwater lake has been in the spotlight for an extreme sport.
Each March since 2005, about 150 people from around the world sign up for the Baikal Ice Marathon. They come to explore the lake’s breathtaking beauty and challenge themselves in unpredictable conditions. The 26-mile (41.84-kilometers) journey starts on the lake’s eastern shore. In March, the ice is a meter thick and iron-hard. Runners cross this frozen surface, finishing on the western side of the lake.
Known as the “blue eye of Siberia”, Lake Baikal has exceptionally clear waters. This means its ice is almost perfectly transparent (透明的). “Seen from above, a runner on the ice looks as if he or she were jogging through space.” The New York Times noted.
The landscape might be beautiful, but it’s also harsh. Strong winds blast (侵袭) across the lake and frostbite can occur within half an hour. Runners say the cold climate is what draws them. They want to test their limits.
“When you are in such an environment, you don’t have cars around you, and you don’t have the noise around. I think these extreme races allow you to be alone with nature.” Alicja Barahona, a 64-year-old runner from the US, told ABC news.
The location offers some strange and unique characteristics for this marathon. The finishing line is visible from the start, but the endless white offers no progress markers. The race also ends with little fanfare (隆重的欢迎). Tourists crowding the ice are mostly addicted to snapping selfies (自拍) and just ignore the runners.
For some runners, the absence of spectators makes the race more challenging, because it’s lonely. They must fight with themselves. “You are alone on Baikal. It is your race. You are alone with yourself. All you need to do is to defeat yourself.” Veronique Messina, a French runner, told the Telegraph.
1.What can we know about the Baikal Ice Marathon from the article?
A. It takes runners from the northern end to the southern end of the lake.
B. It involves extreme weather and beautiful scenery.
C. It attracts more and more participants each year.
D. It is about 26 kilometers in length.
2.How does the Baikal Ice Marathon differ from other marathons?
A. Only men are allowed to run in this race.
B. The runners are often distracted by tourists.
C. There are many progress markers on the ice.
D. The runners can see the finishing line from the start.
3.What is the most challenging part of the race for Messina?
A. The cold climate. B. The long distance.
C. Noisy surroundings. D. Loneliness.
4.How many reasons are listed to show the loneliness?
A. 5. B. 4.
C. 3. D. 2.
高三英语阅读理解中等难度题查看答案及解析
It can be definitely terrifying to fall through ice on a frozen lake. 1.In fact, there is more time to help you survive than you think.
As you first hit the freezing water, you will almost breathe quickly at once. Remember to get control of your breathing and not to move around. 2.This means that it takes about one minute to gain control of your breathing, ten minutes to move before you get too cold. The final one is to remind you that it will take one hour before you become unconscious.
Take that first minute and fully focus on your breathing. Slow it down, and then look around to see if you can locate the thickest area of ice. When you locate the ice, stretch your arms over the surface, and then begin to flutter-kick(上下打水)until your body becomes horizontal with the surface. 3..
It is possible that you can live for several hours after passing out. This, however, does require some planning. You only have about 10 minutes before your muscles and nerves become too cold to work. Besides, what if you feel too weak to go on and you cannot get out?4.The point is to encourage your coat to freeze to the ice, so that if you lose consciousness, you will keep your head out of ice.
5..
A. Remember that you should always stay off ice that’s only 3 inches.
B. Place your arms over the surface of the ice and remain still.
C. It can help to remember the “1-10-1 principle”.
D. However, if you remain calm, it can save your life.
E. Remove any clothing or heavy objects that are weighting you down.
F. Thus you will remain visible for rescue, even if you pass out.
G. Kick hard and use your arms and hands to climb out of the water.
高三英语七选五困难题查看答案及解析
It can be truly terrifying to fall through ice on a frozen lake. 1.In fact, there is more time to help you survive than you think.
As you first hit the freezing water, you will almost breathe quickly at once. Remember to get control of your breathing and not to move around. 2.This means that it takes about one minute to gain control of your breathing ,ten minutes to move before you get too cold. The final one is to remind you that it will take one hour before you become unconscious.
Take that first minute and fully focus on your breathing. Slow it down, and then look around to see if you can locate the thickest area of ice. When you locate the ice, stretch your arms over the surface, and then begin to flutter-kick(上下打水)until your body becomes horizontal with the surface. 3..
It is possible that you can live for several hours after passing out. This, however, does require some planning. You only have about 10 minutes before your muscles and nerves become too cold to work. Besides, what if you feel too weal to go on and you cannot get out?4.The point is to encourage your coat to freeze to the ice, so that if you lose consciousness, you will keep your head out of ice. 5..
A. It can help to remember the “1-10-1 principle”.
B. However, if you remain calm, it can save your life.
C. Remove any clothing or heavy objects that are weighting you down.
D. Thus you will remain visible for rescue, even if you pass out.
E. Kick hard and use your arms and hands to climb out of the water.
F. Remember that you should always stay off ice that’s only 3 inches.
G. Place your arms over the surface of the ice and remain still.
高三英语七选五中等难度题查看答案及解析
Sometimes Chinese English teachers are puzzled by 1. questions, “Have you got any skills in reading comprehension?” Actually, many of the teachers can’t give students 2. efficient way to deal with reading. Anyway, 3. often simply say, “Read more and practise more, and you 4. (get) more experience in reading comprehension.” Frankly, these teachers’ good 5. (suggest) are only helpful to arouse students’ interest in reading 6. not helpful to deal with the questions in the examinations of reading comprehension. Personally, I think the skill for reading comprehension should be based on the knowledge of English writing. 7. the English passages are written under some rules or principles, the science of reading and understanding may have a close relationship with writing. Reading comprehension can’t be independent from the knowledge of writing. So 8. (do) better in reading comprehension, we should learn the knowledge of writing, study 9. questions are designed and the relationship 10. questions and the reading materials.
高三英语其他题中等难度题查看答案及解析
Scientists have long puzzled over how iguanas, a group of lizards(蜥蜴) mostly found in the Americas, came to live in the isolated Pacific islands of Fiji and Tonga. Some scientists used to suppose that they must have traveled there on a raft, a journey of around 5,000 miles from South America to the islands. There are documented cases of iguanas reaching remote Caribbean islands and the Galapagos Islands on floating logs. But new research in January by Brice Noonan and Jack Sites suggested that iguanas may have simply walked to Fiji and Tonga when the islands were still a part of an ancient southern supercontinent.
The ancient supercontinent was made up of present-day Africa, Australia, Antarctica and parts of Asia. If that’s the case, the island species would need to be very old. Using “molecular (分子) clock” analysis of living iguanas’ DNA, Noonan and Sites found that, sure enough, the lineage of iguanas has been around for more than 60 million years—easily old enough to have been in the area when the islands were still connected by land bridges to Asia or Australia.
Fossils (化石) uncovered in Mongolia suggest that iguanid ancestors did once live in Asia. Though there’s currently no fossil evidence of iguanas in Australia, that doesn’t necessarily mean they were never there. “The fossil record of this continent is surprisingly poor and cannot be taken as evidence of true absence,” the authors write.
So if the iguanas simply walked to Fiji and Tonga from Asia or possibly Australia, why are they not also found on the rest of the Pacific islands? Noonan and Sites say fossil evidence suggests that iguana species did once inhabit other islands, but went extinct right around the time when humans settled in those islands. But Fiji and Tonga have a much shorter history of human presence, which may have helped the iguanas living there to escape extinction.
The researchers say that their study can’t completely rule out the rafting theory, but it does make the land bridge theory “far more reasonable than previously thought.”
1. What did some scientists previously believe about the iguanas?
A. They were once discovered in America.
B. They traveled by raft to Fiji and Tonga.
C. They could survive in poor living conditions.
D. They moved to Fiji and Tonga from Australia.
2.According to Noonan and Sites, 60 million years ago ____.
A. the land of the world was a supercontinent
B. Fiji and Tonga were connected to Asia or Australia
C. Africa, Australia and America were a continent
D. iguanas walked to Fiji and Tonga from Africa
3.The underline word “lineage” in Paragraph 2 probably refers to ____.
A. conditions in which creatures can survive
B. the change in ancient plants and animals.
C. the line of generations of an ancestor
D. the habitat of a type of an ancient animal
4. What is the main topic of this passage?
A. The life span of animals living on the ancient supercontinent.
B. The two islands being home to several iguana species in the Pacific region.
C. The fossil evidence suggesting iguanas’ ancestors’ swimming to Fiji and Tonga
D. By raft or by land — how did iguanas reach the tiny Pacific islands?
高三英语阅读理解中等难度题查看答案及解析
Puzzled by this strange natural phenomenon, the scientists started to explore every _______ they knew to figure it out.
A. impression B. intention C. avenue D. design
高三英语单项填空中等难度题查看答案及解析
Scientists have been puzzled by the phenomenon that migrating birds fly not just in groups all the time, but in "V" formations and they have tried to figure out what benefit birds get from this particular formation. Now, a research group from University of London may have found the answer ― migrating birds fly in a "V" to save energy, according to a study published in the journal Nature.
When a bird flaps(振翅) its wings, it stirs the air around it and causes it to move indifferent directions. Scientist found in the study that the air creates an upward-moving wave at the tips of the wings, which means that if a bird flies around the wingtips of another bird, it can get a boost（抬高） from the rising air and therefore use less energy to stay in the air.
Apart form the "free ride" strategy, scientists were also surprised to observe that migrating birds timed their wing beats and adjusted their positions in a very precise way to maximize the lifting effect while avoiding areas where the air move downward.
"They're able to sense what's going on from the bird in front, where this 'good air' is coming from and now how to position themselves perfectly in it," lead researcher Steven Portugal told BBC.
In fact, the "V" formation has long thought to help birds fly more efficiently(效率搞地). A previous study showed that birds' heart rates went down when they were flying together in a "V" formation. Jet fighters were also found to be able reduce their energy use by up to 18% by staying near the wingtips of other jet fighters. Both of these findings led scientists to suspect that the "V" formation had an efficiency purpose, but until now they still lack proof.
"For scientists, the new study provides an insight into an interesting natural phenomenon. But it could mean even more for aircraft companies — helping them understand how they can imitate that with their plane formations to save fuel, said Portugal."
1.What is the author's purpose in writing this article?
A. To explain how birds benefit from migration.
B. To introduce how migrating birds find their way.
C. To tell some applications of migrating birds' "V" formations.
D. To report new findings about migrating birds' "V" formations.
2. According to the recent study, when birds migrate .
A. they don't change their lead birds during the whole journey
B. they fly in "V" formations to protect themselves against enemies
C. they form the shape of a "V" to make best use of the lifting effect
D. the air they stir around makes it hard for the birds behind to fly fast
3.What is the significance of the new study according to this article?
A. It might inspire aircraft companies to think of ways to improve efficiency.
B. It has proved that the "V" formation can improve in efficiency in many fields,
C. It has led scientists to discover that birds' heart rates go down when they fly in a "V".
D. It shows that the best formation of jet fighters in battle should be a "V" formation.
4. The underlined word "imitate" in the last paragraph most probably means " ".
A. use B. copy C. change D. learn
高三英语阅读理解中等难度题查看答案及解析
You must have been troubled by when to say “I love you” because it is one of the greatest puzzles in our life.
What if you say it first and your partner doesn’t love you back? Or if they do say it but you don’t feel they mean it? Being the first to declare your love can be nerve racking(紧张）and risky and can leave you feeling as vulnerable as a turtle with no shell. But is the person who says it first really in a position of weakness? Doesn’t it pay to hold back, play it cool and wait until the other half has shown their hand fast?
A really good relationship should be about “being fair and being equal,” says psychologist Sidney Crown. “But love is seldom equal.” All relationships go through power struggles but, he says, if a love imbalance continues for years, the rot will set in. “That feeling of ‘I’ve always loved you more’ may be subverted(颠覆，破坏) for a time, but it never goes away completely and it often emerges in squabbling(大声争吵).” In love, at least, the silent, withholding type is not always the most powerful. “The strongest one in a relationship is often the person who feels confident enough to talk about their feelings,” says educational psychologist Ingrid Collins. Psychosexual therapist Paula Hall agrees. “The one with the upper hand is often the person who takes the initiative. In fact, the person who says ‘I love you’ first may also be the one who says ‘I’ m bored with you’ first.” Hall believes that much depends on how “I love you” is said and the motivation of the person saying it. “Is it said when they’re drunk? Is it said before their partner files off on holiday, and what it really means is ‘Please don’ t be unfaithful to me’ ?” By saying ‘I love you’, they are really saying ‘Do you love me?’ If so, wouldn’t it just be more honest to say that. Collins agrees that intention is everything. “It’s not what is said, but how it’s said. What it comes down to is the sincerity of the speaker.”
1. What is the main idea of this passage?
A. The importance of “I love you”
B. The meaning of “I love you”
C. The time of saying “I love you”
D. The place of saying “I love you”
2. In the first sentence the author means that _________.
A. it is easy to say “I love you”
B. it is hard to say “I love you”
C. we have many troubles in our life
D. people usually do not know when to say “I love you”
3. According to the expert, a good relationship should be _______.
A. fair and equal B. fair and kind
C. powerful and equal D. confident and fair
4. In the third paragraph, the phrase “with the upper hand” means _________.
A. being low in spirit B. having only one hand
C. being active D. being passive
高三英语阅读理解简单题查看答案及解析
Your remarks seem strange ______ what I have heard about.
A．in relation to B．in relation of C．in connection to D．in connection of
高三英语单项填空中等难度题查看答案及解析