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[主观题]

Deep inside a mountain near Sweatwater in East Tennessee is a body of water known as the L

ost Sea. It is listed by the "Guinness Book of World Records" as the world's largest underground lake. The lost Sea is part of an extensive and historical cave system called Craighead Caverns.

The caverns have been known and used since the days of the Cherokee Indian Nation. The cave expands into a series of huge rooms from a small opening on the side of the mountain. Approximately one mile from the entrance, in a room called "the Council Room", many Indian artifacts have been found. Some of the items discovered include pottery, arrowheads, weapons and jewelry.

For many years there were persistent rumors of a large underground lake somewhere in a cave, but it was not discovered until 1905. In that year, a thirteen-year-old boy named Ben Sands crawled through a small opening three hundred feet underground. He found himself in a large cave half filled with water.

Today tourists visit the Lost Sea and ride far out onto it in glass-bottomed boats powered by electric motors. More than thirteen acres of water have been mapped out so far and still no end to the lake has been found. Even though teams of divers have tried to explore the Lost Sea, the full extent of it is still unknown.

According to the passage, the lost Sea is unique because it is ______.

A．part of a historical cave system

B．the biggest underground lake in the world

C．listed in the "Guinness Book of World Records"

D．the largest body of water in Tennessee

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发布时间：2020-11-30

更多“Deep inside a mountain near Sweatwater in East Tennessee is a body of water known as the L”相关的问题

第1题

With tremendous force a great mass of solid rock suddenly moves deep inside the earth. Sho

ck waves travel upward, and the surface of the earth begins to tremble, ff the trembling is very strong, trees sway and fall, houses collapse, bridges twist and slide into rivers. In cities, fires start as gas lines break. With a loud rear, the ground splits open. Earthquake!

Experts cannot tell when earthquakes will occur. But they can tell us why they happen. In the center of the earth a huge, hot mass moves constantly, like rushing water. Vast areas of solid rock, called plates(板岩), rest on top of this mass. Sometimes two plates move and strain against each other. When they finally break, the earth's surface moves, and an earthquake begins. Some quakes have other causes.

Most of the world's earthquakes happen around or in the Pacific Ocean. Called the "ring of fire" by scientists, this area suffers from about twenty powerful earthquakes each year. But there are others even too small to be felt. They occur a million times a year. However, they take place under the ocean or away from people. Therefore, there is no damage.

Scientists measure the strength of earthquakes with sensitive machines called seismographs(地震仪). These instruments can record shock waves from earthquakes in any part of the world. Seismographs show us that some earthquakes can give off as much energy as 200 million tons of TNT. That is 10,000 times stronger than an atomic bomb!

Powerful earthquakes can sometimes take an enormous number of human lives. The worst earthquake on record took place in China in 1556. At that time 830,000 people died. In 1737, 300,000 were killed during an earthquake in India. In modern times, China was hit again with the world's second worst quake in 1976. It left 650,000 dead.

Many cities are taking steps to prevent loss of life in earthquakes. Buildings are being made quakeproof. Rescue teams practice saving victims. Partly because of such steps, the 1989 San Francisco quake took only sixty lives.

We can infer from the passage that ______.

A．a great mass of solid rock suddenly moves deep inside the earth

B．earthquake usually does great damage to human beings

C．earthquake cannot be measured

D．earthquake takes place with a loud roar

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第2题

听力原文：Diamonds are the hardest substance known on Earth and they make sparkling jewelry

听力原文： Diamonds are the hardest substance known on Earth and they make sparkling jewelry as well as sawblades that can cut through pretty much anything. They form. deep within the Earth's mantle layer (about 200 km deep ) when atoms of the element carbon arrange themselves into a lattice under huge amounts of pressure from the load of rocks above.

Recently, geologists studying diamonds have identified the ages of thousands of diamonds from Southern Africa, where the mineral is most abundant. Their research found that there were only three times in Earth's history when diamonds were made and that the Earth no longer makes diamonds like it used to. Something was different then. Perhaps the planet was hotter on the inside, or the composition of the rocks was subtly different. "Whatever it was it has changed now," stated Steve Shirey of the Carnegie Institution in Washington, D.C., one of the project researchers.

The oldest diamonds were made 3.3 billion years ago when Earth was relatively young. The second time diamonds formed was 2.9 billion years ago. The youngest diamonds on Earth are 1.2 billion years old although a few smaller diamonds are about 100 million years old. Small bits of rock within those diamonds, called impurities, indicate that they probably formed from rocks laid down in a shallow sea suggesting that the carbon that made the diamonds probably came from the remains of ancient sea life.

Some people like diamonds because they are pretty, rare, or expensive but Dr. Steve Shiley has a different perspective. "I think of diamonds," he said, "as being tiny time capsules that encase a little piece of rock protecting it for billions of years and providing us with a unique window on ancient times."

(33)

A．Always.

B．Once.

C．Twice.

D．Three times.

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第3题

How to Deal with Loneliness ALoneliness is a feeling of emptiness or hollowness inside you

How to Deal with Loneliness

Loneliness is a feeling of emptiness or hollowness inside you. You feel isolated or separated from the world, cut off from those you would like to have contact with. There are different kinds of loneliness and different degrees of the loneliness. You might experience loneliness as a vague feeling that something is not right, a kind of minor emptiness. Or you might feel loneliness as a very intense deprivation and deep pain, One type of loneliness might be related to missing a specific individual because they have died or because they are actually physically isolated from. For instance, if you work alone on the night shift or are alone in a part of a building where people seldom go. You might even feel emotionally isolated when you are surrounded by people but are having difficulty reaching out to them.

It needs to be emphasized here that loneliness is not the same as being alone. A person will always have time when they chose to be alone. Rather, loneliness is the feeling of being alone and feeling sad about it. And, of course, all of us feel lonely some of the time. It is only when we seem trapped in our loneliness that it becomes a real problem.

Loneliness is a passive state. That is, it is maintained by our passively letting it continue and doing nothing to change it. We hope it will go away, eventually, and we do nothing but let it envelop us. Strangely, there are times when we might even embrace the feeling. Yet, embracing loneliness and sinking down into feeling associated with it usually leads to a sense of depression and helplessness, which, in turn, leads to an even more passive state and more depression.

To stop feeling lonely, we first must accept that we are feeling lonely. Sometimes admitting that to ourselves is difficult. We then have to express those feelings of loneliness in some way. We might find ourselves writing in a diary, writing an imaginary letter to a friend or relative, drawing or painting a picture, making up a song, or doing anything else that lets us begin to express the feeling we have inside usincluding talking with other people! Expressing our feelings might lead us to discover that we feel a number of things which might be connected to our feelings of loneliness, including sadness, anger and frustration. We might be able to begin to see where these feelings are coming fromwhat they are connected to in our lives. As we begin to see the connections we will be more able to begin to make changes.

The big change, of course, is to stop being passive and become more active. If we're missing someone, such as parents, family, or friends, we can telephone, write, email or visit them. Talking to an understanding friend can often help change our moods as well. If we don't have an understanding friend, talking with a pastor, teacher or counselor might be a place to start. If we are lonely because we are missing someone who has died, being able to express our grief at their loss and beginning to remember our happier moments with them and knowing that those memories can always be with us, can move us away from the lonely feelings. This can also apply to losses of significant friendships or lovers.

Getting involved in some

A．Y

B．N

C．NG

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第4题

Centuries ago, during the Middle Ages, most of the land in Europe was owned by many differ

ent kings and queens, princes and princesses, and lords and ladies. They did not all get along. They were always fighting. They all wanted to get more land. To protect themselves, they started building huge homes out of stone. They called their homes castles.

A castle was built behind a strong stone wall. The wall was five or six feet thick and ten to twenty feet high. A deep ditch called a moat was dug around the outside of the wall. It was often filled with water, and the only way anyone could enter the castle was to cross a drawbridge. The drawbridge could be raised or lowered over the moat from inside the castle walls. There was also a tunnel that began in the castle and ended at the moat. This was important in case the castle was captured. It allowed the king and queen to escape. They could swim across the moat and hide in the forest.

Living in a castle was not very comfortable. The rooms were cold and damp. Every room could have' a fire burning in a great fireplace, but until the twelfth century castles did not have chimneys. The smoke from their fireplaces had to go out through open doors and windows. Meals often had ten or twelve courses. The meat might be wild bear or birds that were boiled or roasted over an open fire. All the food was highly seasoned. People even put pepper in their drinks[ The people sat at a long table and ate with their fingers and a knife, all picking their food from the same big dish. They had no napkins. Therefore, they often wiped their hands on pieces of bread. When their fingers were clean, they threw the bread to their bunting dogs.

Which of the following statements is NOT true about castles？

A．Kings and queens, princes and princesses, and lords and ladies built castles in order to get more land.

B．Around the outside of a castle, a moat was dug, which was often filled with water.

C．A castle was built behind a thick and high stone wall, which was strong enough to stand the possible attack of enemies.

D．If a drawbridge was pulled up, there was no way for people to enter the castle.

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第5题

It was a chilly November evening in New York City, and my daughter and I were walking

up Broadway.Nora noticed a guy sitting inside a cardboard box next to a newsstand.She pulled at my coat sleeve and said, “That man's cold, Daddy.Can we take him home？”

I don't remember my reply, but I do remember a sudden heavy feeling inside me.I had always been delighted at how much my daughter noticed in her world, whether it was birds in flight or children playing.But now she was noticing suffering and poverty.She wasn't even four.

A few days later, I saw an article in the newspaper about volunteers who delivered meals to elderly people.The volunteers went to a nearby school on a Sunday morning, picked up a food package, and delivered it to an elderly person.I signed us up.Nora was excited about it.She could understand the importance of food, so she could easily see how valuable our job was.When Sunday came, we picked up the package and phoned the elderly person we'd been assigned.She invited us right over.

The building was depressing.When the door opened, facing us was a silver-haired woman in an old dress.She took the package and asked if we would like to come in.Nora ran inside.I reluctantly followed.Our hostess showed us some photos of her family.Nora played and laughed.I accepted a second cup of tea.When it came time to say good-bye, we three stood in the doorway and hugged.I walked home in tears.

Where else but as volunteers do you have the opportunity to do something enjoyable that's good for yourself as well as for others？ Indeed, the poverty my daughter and I helped lessen that Sunday afternoon was not the woman's alone — it was in our lives, too.Now Nora and I regularly serve meals to needy people and collect clothes for the homeless.Yet, as I've watched her grow over these past four years, I still wonder — which of us has benefited more？

26.The man Nora noticed on that evening was probably ______.

A.asking for food

B.one of those homeless

C.taken home by the author

D.buying a newspaper

27.The author had a sudden heavy feeling (Para.2), because ______.

A.his daughter had noticed the dark side of life

B.he did not want to take the guy home

C.he felt a deep sympathy for the guy

D.his daughter was afraid of what she saw

28.Their volunteer job was to ______.

A.visit poor homes

B.serve meals at a nearby school

C.pick up packages for poor, elderly people

D.deliver food to needy, elderly people

29.The word “us” in the last paragraph refers to ______ .

A.the author and the old woman

B.the giver and receiver of the help

C.the author and his daughter

D.the author and the guy in the box

30.The best title for this passage might be “______.”

A.A Loving Kid

B.A Lesson in Caring

C.Volunteers at Work

D.How to Help the Needy

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第6题

听力原文：Centuries ago, during the Middle Ages, most of the land in Europe was owned by ma

听力原文： Centuries ago, during the Middle Ages, most of the land in Europe was owned by many different kings and queens, princes and princesses, and lords and ladies. They did not all get along. They were always fighting. They all wanted to get more land. To protect themselves, they started building huge homes out of stone. They called their homes castles.

A castle was built behind a strong stonewall. The wall was five or six feet thick and ten to twenty feet high. A deep ditch called a moat was dug around the outside of the wall. It was often filled with water, and the only way anyone could enter the castle was to cross a drawbridge. The drawbridge could be raised or lowered over the moat from inside the castle walls. There was also a tunnel that began in the castle and ended at the moat. This was important in case the castle was captured. It allowed the king and queen to escape. They could swim across the moat and hide in the forest.

Living in a castle was not very comfortable. The rooms were cold and damp. Every room could have a fire burning in a great fireplace, but until the twelfth century castles did not have chimneys. The smoke from their fireplaces had to go out through open doors, and windows.

Meals often had ten or twelve courses. The meat might be wild bears or birds that were boiled or roasted over an open fire. All the food was highly seasoned. People even put pepper in their drinks!

The people sat at a long table and ate with their fingers and a knife, all picking their food from the same big dish. They had no napkins. Therefore, they often wiped their hands on pieces of bread. When their fingers were clean, they threw the bread to their hunting dogs.

(30)

A．Kings and queens, princes and princesses, and lords and ladies built castles in order to get more land.

B．Around the outside of a castle, a moat was dug, which was often filled with water.

C．A castle was built behind a thick and high stonewall, which was strong enough to stand the possible attack of enemies.

D．If a drawbridge was pulled up, there was no way for people to enter the castle.

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第7题

Where Do Dreams Come from？Do you often dream at night？ Most people do. When they wake in t

Where Do Dreams Come from？

Do you often dream at night？ Most people do. When they wake in the morning they say to them selves, "What a strange dream I had! I wonder what made me dream that."

Sometimes dreams are frightening. Terrible creatures threaten and pursue us. Sometimes, in dreams, wishes come tree. We can fly through the air or float from mountain-tops. At other times we are troubled by dreams in which everything is confused. We are lost and can't find our way home. The world seems to have been turned upside-down and nothing makes sense.

In dreams we act very strangely. We do, things which we would never do when we're awake. We think and say things we would never think and say. Why are dreams so strange？ Where do dreams come from？

People have been trying to answer this since the beginning of time. But no one has produced a more satisfying answer than a man called Sigmund Freud. One's dream-world seems strange and unfamiliar, he said, because dreams come from a part of one's mind which one can neither recognise nor control. He named this the "unconscious mind".

Sigmund Freud was born about a hundred years ago. He lived most of his life in Vienna, Austria, but ended his days in London, soon after the beginning of the Second World War.

Freud was one of the great explorers of our time. But the new worlds he explored were inside man himself. For the unconscious mind is like a deep well, full of memories and feelings. These memories and feelings have been stored there from the moment of our birth—perhaps even before birth. Our conscious mind has forgotten them. We do not suspect that they are there until some unhappy or unusual experlence causes us to remember, or to dream dreams. Then suddenly we see a face we had forgotten long ago. We feel the same jealous fear and bitter disappointments we felt when we were little children.

This discovery of Freud's is very important ff we wish to understand why people act as they do. For the unconscious forces inside us are at least as powerful as the conscious forces we know about. Why do we choose one friend rather than another？ Why does one story make us cry or laugh while another story doesn't affect us at all？ Perhaps we know why. If we don't, the reasons may lie deep in our unconscious minds.

When Freud was a child he wanted to become a great soldier and win honour for his country. At that time Austria and Germany were at war with each other. His father used to take Sigmund down to the rail way station to watch the trains come in from the battle-fields. The trains were full of wounded soldiers. There were men who had lost all eye, an arm or a leg fighting in tile war. Many of the soldiers were suffering great pain.

Young Sigmund watched the wounded men as they were moved from the trains into the hay-carts that carried them to the hospital. He was very sorry for them. He pitied them so much that he said to the teacher at his school, "Let us boys make bandages for the poor soldiers as our sisters in the girls' school do."

Even then, Freud cared about the sufferings of others, so it isn't surprising that he became a doctor when he grew up. Like other doctors he learned all about the way in which the human body works. But he became more and more curious about the human mind. He went to Pads to study with a famous French doctor, Charcot. Charcot's special study was diseases of the mind and nerves.

At that time it seemed that no one knew very much about tile mind. If a person went mad, or "out of his mind" ,there was not much that could be done about it. There was little help or comfort for the madman or his family. People didn't understand at all what was happening to him. Had be been possessed by a devil or evil spirit？ Was God punishing him for wrongdoing？ Often such people were shut away from the company of ordinary civi

A．Y

B．N

C．NG

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第8题

Large animals that inhabit the desert have evolved a number of adaptations for reducing th

e effects of extreme heat. One adaptation is to be light in color, and to reflect rather than absorb the Sun's rays. Desert mammals also depart from the normal mammalian practice of maintaining a constant body temperature. Instead of trying to keep down the body temperature deep inside the body, which would involve the expenditure of water and energy, desert mammals allow their temperatures to rise to what would normally be fever height, and temperatures as high as 46 degrees Celsius have been measured in Grant's gazelles. The overheated body then cools down during the cold desert night, and indeed the temperature may fall unusually low by dawn, as low as 34 degrees Celsius in the camel. This is an advantage since the heat of the first few hours of daylight is absorbed in warming up the body, and an excessive buildup of heat does not begin until well into the day.

Another strategy of large desert animals is to tolerate the loss of body water to a point that would be fatal for non-adapted animals. The camel can lose up to 30 percent of its body weight as water without harm to itself, whereas human beings die after losing only 12 to 13 percent of their body weight. An equally important adaptation is the ability to replenish (Sheik) this water loss at one drink. Desert animals can drink huge volumes in a short time, and camels have been known to imbibe (吸收) over 100 liters in a few minutes. A very dehydrated person, on the other hand, cannot drink enough water to rehydrate at one session, because the human stomach is not sufficiently big and because a too rapid dilution of the body fluids causes death from water intoxication. The tolerance of water loss is of obvious advantage in the desert, as animals do not have to remain near a water hole but can obtain food from grazing sparse pastures. Desert-adapted mammals have the further ability to feed normally when extremely dehydrated, it is a common experience in people that appetite is lost even under conditions of moderate thirst.

What is the passage mainly about？

A．Animals developed different strategies to survive.

B．Large animals can take strategies to reduce the effect of extreme heat.

C．Animals can tolerate the loss of body water.

D．A very dehydrated person can drink enough water to rehydrate.

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第9题

Diamonds are just carbon in its most concentrated form, the element that makes up 18 perce

nt of the weight of your body. There is no other gemstone as cherished as the diamond, but in truth, diamonds are no rarer than many other precious gems. They continue to demand higher market prices because the majority of the diamond market is controlled by a single entity.

The Origin of Diamonds

Carbon is one of the most common elements in the world, and is one of the four essentials for the existence of life. Humans are more than 18-percent carbon. When occurring in nature, carbon exists in three basic forms, of which diamond is an extremely hard, clear crystal.

Diamonds form. about 161 km below the Earth's surface, in the molten rock of the Earth's mantle, which provides the right amounts of pressure and heat to transform. carbon into a diamond. In order for a diamond to be created, carbon must be placed under at least 435,113 pounds per square inch (psi) of pressure at a temperature of at least 400 Celsius. If conditions drop below either of these two points, graphite will be created. At depths of 150 km or more, pressure builds to about 725,189 psi and heat can exceed 1,200 C.

Kimberlite Pipes

Most diamonds that we see today were formed millions (if not billions) of years ago. Powerful magma eruptions brought the diamonds to the surface, creating kimberlite pipes. Kimberlite is named after Kimberly, South Africa, where these pipes were first found. Most of these eruptions occurred between 1,100 million and 20 million years ago.

Kimberlite pipes are created as magma (岩浆) flows through deep fractures in the Earth. The magma inside the kimberlite pipes acts like an elevator, pushing the diamonds and other rocks and minerals through the mantle and crust in just a few hours. These eruptions were short, but many times more powerful than volcanic eruptions that happen today.

The magma eventually cooled inside these kimberlite pipes, leaving behind conical veins of kimberlite rock that contain diamonds. Kimberlite is a bluish rock that diamond miners look for when seeking out new diamond deposits. The surface area of diamond-bearing kimberlite pipes ranges from 2 to 146 hectares. Diamonds may also be found in river beds, which are called alluvial diamond sites. These are diamonds that originate in kimberlite pipes, but get moved by geological activity. Glaciers and water can also move diamonds thousands of miles from their original location.

Cutting Diamonds

There are special techniques that are used to cut and shape a diamond before it gets to the jewelry store. Diamond cutters first try to remove any impurities or irregularities in the diamond. Sometimes, diamonds have to be sawed with the use of a phosphor-bronze blade or laser. Then the diamond is rubbed by another diamond to create facets-tiny flat spots on the surface. Finally, the diamond is pressed against a rotating polishing wheel to give the diamond its finished look.

Rating Diamonds

Diamonds are judged on several factors that determine their beauty. Most diamonds never reach the consumer market because they are too flawed. Often, these diamonds are used for industrial purposes--as an abrasive, for drill bits or for cutting diamonds and other gems. If you've ever purchased a diamond, you've heard of the "4 Cs:"

1. Cut--This refers to how the diamond has been cut and its geometric proportions. When a diamond is cut, facets are created and the diamond's finished shape is determined.

2. Clarity

A．Y

B．N

C．NG

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第10题

Creatures of the Thermal （热量的) VentsThe three-person submersible Alvin sank through the

Creatures of the Thermal (热量的) Vents

The three-person submersible Alvin sank through the cold, dark waters of the Pacific Ocean for more than an hour, finally touching down on the sea floor more than 8,000 feet below the surface. It was December 1993, and the scientists inside the sub had come to thisstretch of the East Pacific Rise, an underwater mountain range about 500 miles southwest of Acapulco, Mexico, to inspect a recently formed hydrothermal vent--a fissure(裂缝) in the ocean bottom that leaks boiling, acidic water.

Peering out through the sub's tiny windows, the visitors were astonished to see thickets of giant tube worms, some four feet tall. The tail ends of the worms were firmly planted on the ocean floor, while red plumes on the other ends swayed like a field of poppies. Alvin had brought researches to the same spot less than two years earlier, when they had seen none of these strange creatures. Previous measurements showed that individual tube worms could increase in length at a rate of 33 inches per year, making them the fastest-growing marine invertebrates. That means tube worms can grow more rapidly than scientists once thought.

The giant tube worm is one of the most eye-catching members of a diverse community that forms around hydrothermal vents. Scientists once thought that no living thing could survive the harsh combination of toxic chemicals, high temperatures, high pressures, and total darkness at these vents. But in 1977, researchers diving in Alvin discovered tube worms and other strange organisms thriving at a Vent off the Galapagos Islands. Similar communities have since been found at several hundred hot sots around the world. These creatures are like nothing else on Earth.

Vents form. where the planet's crustal plates are slowly spreading apart and magma is welling up from below to form. mountain ranges known as mid-ocean ridges. As cracks form. at these spreading centers, seawater seeps a mile or two down into the hot rock. Enriched with minerals leached from the rock, the water heats and rises to the ocean floor to form. a vent. Vents are usually clustered in fields, underwater versions of Yellowstone's geyser basins. Individual vent openings typically range from less than a half inch to more than six feet in diameter. Such fields are normally found at a depth of more than a mile. Most have been discovered along the crest of the Mid-Oceanic Ridge, a 46,000-mile-long chain of mountains that wraps around Earth like the seams on a baseball. A few vents have also been found at seamounts, underwater volcanoes that are not located at the intersection of crustal plates.

Hydrothermal vents are underwater oases (避风港), providing habitat for many creatures that are not found anywhere else in the ocean. Water pouring out of vents can reach temperatures up to about 400℃; the high pressure keeps the water from boiling. However, the intense heat is limited to a small area. Within less than an inch of the vent opening, the water temperature drops to 2℃, the ambient temperature of deep seawater. Most of the creatures that assemble around vents live at temperatures just above freezing. Thus, chemicals are the key to vent life, not heat. The most prevalent chemical dissolved in vent water is hydrogen sulfide (硫化氢), which smells like rotten eggs. This chemical is produced when seawater reacts with sulfate (硫酸盐) in the rocks below the ocean floor. Vent bacteria use hydrogen sulfide as their energy source instead of sunlight. The bacteria in turn sustain large organisms in the vent community.

The clams, mussels, tube worms, and other creatures at the vent have a symbiotic relationship (共生关系) with bacteria. The giant tube worms, for example, have no digestive system--no mouth or gut. The worm depends virtually solely on the bacteria for its nutrition and both partners benefit. The brown, spongy tissue filling the inside of a tube

A．Y

B．N

C．NG

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