相關(guān)習(xí)題
 0  5259  5267  5273  5277  5283  5285  5289  5295  5297  5303  5309  5313  5315  5319  5325  5327  5333  5337  5339  5343  5345  5349  5351  5353  5354  5355  5357  5358  5359  5361  5363  5367  5369  5373  5375  5379  5385  5387  5393  5397  5399  5403  5409  5415  5417  5423  5427  5429  5435  5439  5445  5453  151629 

科目: 來源: 題型:閱讀理解

By the mid-nineteenth century, the term "icebox" had entered the American language, but ice was still only beginning to affect the diet of ordinary citizens in the United States. The ice trade grew with the growth of cities. Ice was used in hotels, taverns(酒館), and hospitals, and by some forward-looking city dealers in fresh meat, fresh fish, and butter. After the Civil War (1861-1865), as ice was used to refrigerate freight cars, it also came into household use. Even before 1880, half of the ice sold in New York, Philadelphia, and Baltimore, and one-third of that sold in Boston and Chicago, went to families for their own use. This had become possible because a new household convenience, the icebox, a precursor (前身) of the modern fridge, had been invented.
Making an efficient icebox as not as easy as we might now suppose. In the early nineteenth century, the knowledge of the physics of heat, which was essential to a science of refrigeration, was rudimentary(未發(fā)展的). The commonsense notion that the best icebox was one that prevented the ice from melting was of course mistaken, for it was the melting of the ice that performed the cooling. Nevertheless, early efforts to economize ice included wrapping up the ice in blankets, which kept the ice from doing its job. Not until near the end of the nineteenth century did inventors achieve the delicate balance of insulation(絕緣) and circulation needed for an efficient icebox.
But as early as 1803, and ingenious Maryland farmer, Thomas Moore, had been on the right track. He owned a farm about twenty miles outside the city of Washington, for which the village of Georgetown was the market center. When he used an icebox of his own design to transport his butter to market, he found that customers would pass up the rapidly melting stuff in the tubs of his competitors to pay a premium price(高價) for his butter, still fresh and hard in neat, one-pound bricks. One advantage of his icebox, Moore explained, was that farmers would no longer have to travel to market at night in order to keep their produce cool.

  1. 1.

    Where was ice used after the Civil War?

    1. A.
      In refrigerating freight cars and households.
    2. B.
      In hotels, taverns and hospitals
    3. C.
      In families of New York, Philadelphia, and Baltimore.
    4. D.
      In fresh meat, fish and butter by city dealers.
  2. 2.

    What was essential to to make an icebox efficient according to the passage?

    1. A.
      Keeping the ice from melting
    2. B.
      Knowledge of the physics of heat.
    3. C.
      Balance of insulation and circulation
    4. D.
      Making efforts to reduce the use of ice
  3. 3.

    The second paragraph is mainly about_____

    1. A.
      the deveopment of icebox
    2. B.
      the theoretical foundation of icebox
    3. C.
      the wrong ideas about icebox
    4. D.
      the way of using icebox
  4. 4.

    What can we infer from the text?

    1. A.
      Thomas Moore is the inventor of modern fridge
    2. B.
      The butter produced by Thomas Moored is better in quality than other famers’
    3. C.
      Knowledge of the physics of heat plays an important part in inventing a good icebox
    4. D.
      Before 1880, most of the sold ice was used for family use.
  5. 5.

    Without an ice box, farmers had to go to the market at night ________.

    1. A.
      to sell their produce at high price
    2. B.
      to go home earlier
    3. C.
      to keep their produce fresh
    4. D.
      to win more customers than their competitors

查看答案和解析>>

科目: 來源: 題型:閱讀理解

The 47-year-old singer talks about the new album Symphony(交響樂) that came out of a “very dark time”, including her decision to give up trying to have children. “People have suggested I could adopt,” Brightman says. “But work is central to my life now. And so I am going to put it to one side. After a while not having children becomes the norm and perhaps that might sound alarming, to parents especially, but I have never known anything different. I’m not hurt by not having children. My life and career are incredibly rich.”
Talking about growing up in a large family in Berkhamsted (father a property developer who later committed suicide), she says: “I was gifted as a child, and very musical. I seemed to be good at anything to do with the arts. At 5,I understood the music I was dancing to and had an eye for costume.” She first appeared in a West End musical at 11 and hated boarding school.
Brightman led the saucy dance troupe(辣妹三人舞) Hot Gossip and had her first hit with I Lost My Heart to a Starship Trooper in 1978. At 18 she married a music manager called Andrew Graham Stewart. “I was probably in love but I can’t remember. Girls change such a lot between 18 and 22. It didn’t really work out.” In 1981 she was spotted by Lloyd Webber. She became his leading lady in Song and Dance, Requiem and Phantom of the Opera. They married in 1984.
Brightman says she felt hostility(敵意) “from the beginning. I haven’t tried to understand it. I’ve done very well everywhere else, especially the US, where I now live, I just accept it for what it is. The more you are away from Britain, the more you appreciate it. But I don’t miss it, although I miss my family. Our profession can be uncomfortable but I enjoy what I do. I get on with it.”

  1. 1.

    The first paragraph tells us that _____.

    1. A.
      Brightman is very popular around the world except in America
    2. B.
      Brightman’s musical style is a mixture of opera, pop and jazz
    3. C.
      the British people don’t like her for her style of music
    4. D.
      Brightman is much older than Andrew Lloyd Webber
  2. 2.

    Brightman decided to give up having children because _____.

    1. A.
      she could adopt one
    2. B.
      her life and career were unbelievably rich without children
    3. C.
      she felt it normal not to have children
    4. D.
      she was too busy
  3. 3.

    The following statements are true except _____.

    1. A.
      Brightman first appeared in a West End musical at 5
    2. B.
      Brightman disliked life on the campus
    3. C.
      Brightman was very gifted when she was young
    4. D.
      The saucy dance troupe made Brightman famous
  4. 4.

    The underlined word in the fourth paragraph probably means _____.

    1. A.
      located
    2. B.
      admired
    3. C.
      followed
    4. D.
      found
  5. 5.

    What does the author try to say in the last paragraph by quoting Brightman’s words?

    1. A.
      Brightman has to accept the fact that she is not liked in Britain
    2. B.
      Brightman lives in America but she loves her own country
    3. C.
      The British coldness towards Brightman led to her hatred to her homeland
    4. D.
      Brightman was at a loss why she was not welcome in Britain

查看答案和解析>>

科目: 來源: 題型:閱讀理解

One warm September night, Mira had come down to the beach to enjoy the night air. She closed her eyes and listened to the waves. Suddenly, she could hear another sound, so she opened her eyes and looked down at the sand. It was moving! All of a sudden she could see a tiny head coming out. Then a turtle(龜) appeared! One by one they struggled out of their underground nests. Mira looked in surprise at the baby turtles.
Mira knew the turtles should head towards the waves and swim away, so she was puzzled when they began to pull themselves towards the dunes(沙丘). Suddenly, she remembered something her grandmother had told her.
“Sea turtles bury their eggs on the beach every year in April and in September. Those baby turtles hatch(孵出) and head back down to the sea. But some of them never make it. Sometimes they die going across the dunes, trying to find those bright lights on the houses. Every day there are more houses being built on the dunes. That means more and more lights to confuse the sea turtles.”
Mira looked out across the dunes at her house. Mira saw her mother and father, sitting on the porch(門廊). She could see them because her house had two bright lights that lit up the porch.
Mira began to run to her house and shouted, “The turtles are hatching! We have to help the turtles!” With these words, Mira ran into the house and turned off the bright porch lights.
In a rush she was off running down the dunes with her whole family following her. They reached the beach just in time to see the tiny turtles slipping silently into the waves. Mira watched as the last turtle entered the water. As the turtle swam away, it looked back at Mira. In the moonlight, Mira thought she saw it smile.

  1. 1.

    Where did the story happen?

    1. A.
      On a beach at night
    2. B.
      In a house near the dunes.
    3. C.
      On a front porch in the evening.
    4. D.
      In the shallow water of the ocean.
  2. 2.

    How did Mira feel when she saw the baby turtles appear?

    1. A.
      Proud.
    2. B.
      Sad.
    3. C.
      Confused.
    4. D.
      Surprised.
  3. 3.

    How did Mira know the lights confused the turtles?

    1. A.
      She read it in a book.
    2. B.
      Her grandmother told her.
    3. C.
      She learned about the turtles at school.
    4. D.
      Her parents taught her about the turtles.
  4. 4.

    Why did Mira run to her house?

    1. A.
      To get a flashlight
    2. B.
      To turn off the porch light.
    3. C.
      To communicate with her parents.
    4. D.
      To ask her grandmother about the lights.
  5. 5.

    This story is mainly about a girl ________.

    1. A.
      enjoying the ocean
    2. B.
      turning lights off at night
    3. C.
      saving the baby turtles
    4. D.
      learning from her grandparents

查看答案和解析>>

科目: 來源: 題型:閱讀理解

A mobile phone is no longer just a phone -- it is also a music player, video camera and personal organizer. And mobile phones with television programming are just around the corner. But the more functions cell phone manufacturers add, the greater the amount of power the phones use and the less practical running them on lithium (鋰) batteries becomes -- so the race to find a viable alternative is on.
Two of the world's biggest electronics makers, Hitachi and Toshiba, are currently competing against each other to come up with an alternative, most likely to be micro fuel cells. The task has been set by Japan's second largest mobile phone provider, KDDI, which wants its customers to soon be able to use special television programming on their handsets, and has asked the two electronics companies to come up with a better power source. Hitomi Murakami, of KDDI, says battery-operated mobile phones cannot keep up with the new applications. "We're looking at various ways to expand content and services that we can provide to the people. And we don't want to have battery issues delaying us from doing that," he says.
Hitachi's Atsushi Morihara says it is a critical race for both of the companies as the resulting product will have a major impact on the mobile market in the future. "We are in competition and it's up to both of us to come up with a good product. A product that will satisfy KDDI's needs. I think I can go as far to say that the winner will take all."
Miniaturized direct methanol (甲醇) fuel cells are different batteries in that they create power instead of simply storing it. That power is made by new technology utilizing cheap methanol. If all gees to plan, come 2007, Japanese phone users will not use an electric charger to power their mobiles, they will instead carry a small bottle of methanol and with just a few squirts, they will have power for their phones. But the method has its downsides, including how passengers will be able to take small mounts of flammable methanol on airliners. Fumio Ueno of Toshiba says that once developed, the uses of miniaturized direct methanol fuel cells have endless possibilities.

  1. 1.

    The lithium batteries are becoming improper for the cell phone because ______.

    1. A.
      there is a television in the phone
    2. B.
      it is inconvenient to use
    3. C.
      it can't provide enough power
    4. D.
      people have found substitutes
  2. 2.

    According to the passage, Toshiba ______.

    1. A.
      is in critical competition with KDDI
    2. B.
      will probably beat its rival
    3. C.
      attaches great importance to methanol fuel
    4. D.
      is one of the largest battery provider
  3. 3.

    Which of the following is NOT the characteristic of methanol fuel?

    1. A.
      Easy to catch fire.
    2. B.
      Portable.
    3. C.
      Inexpensive.
    4. D.
      Available everywhere.
  4. 4.

    The best title for the passage is ______.

    1. A.
      Search for better phone power.
    2. B.
      Development of cell phone battery.
    3. C.
      Competition between two electronic firms.
    4. D.
      Advantage and disadvantage of methanol fuel.

查看答案和解析>>

科目: 來源: 題型:閱讀理解

Every human being has a unique arrangement of the skin on his fingers and this arrangement is unchangeable. Scientists and experts have proved the uniqueness of finger-prints and discovered that no exactly similar pattern is passed on from parents to children, though nobody knows why this is the case.
The ridge structure on a person’s fingers does not change with growth and is not affected by surface injuries. Burns, cuts and other damage to the outer part of the skin will be replaced in time by new one, which bears a reproduction of the original pattern. It is only when the inner skin is injured that the arrangement will be destroyed. Some criminals make use of this fact to remove their own finger-prints but this is a dangerous and rare step to take.
Finger-prints can be made very easily with printer’s ink. They can by recorded easily. With special methods, identification can be achieved successfully within a short time. Because of the simplicity and economy of this system, finger-prints have often been used as a method of solving criminal case. A suspected man may deny a charge but this may be in vain. His finger-prints can prove who he is even if his appearance has been changed by age or accident.
When a suspect leaves finger-prints behind at the scene of a crime, they are difficult to detect with the naked eye. Special techniques are used to “develop” them. Some of the marks found are incomplete but identification is possible if a print of a quarter of an inch square can be obtained.
Notes:
①    unique  adj. 唯一的,獨特的
②    original  adj. 最初的,原始的
③    identification  n. 辯認(rèn),鑒定

  1. 1.

    Scientists and experts have proved that the pattern of a human being’s finger skin ________.

    1. A.
      is similar to his mother’s
    2. B.
      is valuable to himself only
    3. C.
      is like that of others with the same type of blood
    4. D.
      is different from that of all others
  2. 2.

    If your fingers are wounded by knife, fire or other means, the structure of skin will ________.

    1. A.
      be changed partly
    2. B.
      be replaced by a different one
    3. C.
      be the same when the wound is recovered
    4. D.
      become ugly
  3. 3.

    Some criminals remove their own finger-prints by ________.

    1. A.
      using printer’s ink
    2. B.
      injuring the inner skin
    3. C.
      damaging the outer skin
    4. D.
      damaging the colour
  4. 4.

    Finger-prints have often been used as a method of solving criminal case because it ________.

    1. A.
      is complicated but reliable
    2. B.
      is simple and not expensive
    3. C.
      is expensive but easy to do
    4. D.
      can bring a lot of money

查看答案和解析>>

科目: 來源: 題型:閱讀理解

Building after building under water.Refugees in shelters.Thousands of others unsure where to go.Bodies in streets.This is what one of America's historic cities was reduced to this week by a powerful storm, Katrina(卡特里娜).The mayor of New Orleans says thousands may be dead.Hurricane Katrina also caused death and destruction in parts of Mississippi and Alabama along the Gulf of Mexico.
New Orleans is famous for its wild Mardi Gras celebrations.New Orleans is also a major port for foreign oil and other shipping trade.Yet the city of nearly five hundred thousand people was built below sea level.New Orleans has depended on levees to control floods from the Mississippi River.Katrina struck on Monday.New Orleans avoided a direct hit.But two of the levees failed the next day.Most of the city was flooded.Helicopters dropped huge sandbags to fill the breaks.But the water had no place to go.Pumping stations had no power.
America faces one of the worst natural events in its history.President Bush says the recovery will take years.People were told to leave the path of the storm.But some would not or could not.Many of those worst affected by Katrina are poor and black.African-American leaders and others were angry that government aid did not arrive faster.President Bush visited some of the damaged areas on Friday.He said the way officials reacted to the crisis was unacceptable.

  1. 1.

    Which is true of the following details about New Orleans?

    1. A.
      New Orleans is a newly-built city of America
    2. B.
      There were no black people in New Orleans.
    3. C.
      This is the first time that hurricane has stricken it.
    4. D.
      New Orleans is a major port for foreign oil and other shipping trade.
  2. 2.

    What does the underlined word “l(fā)evees”(in the second paragraph) mean?

    1. A.
      trees
    2. B.
      dams
    3. C.
      ports
    4. D.
      ships
  3. 3.

    Which is right about the Hurricane Katrina?

    1. A.
      It also caused the destruction in parts of Mississippi.
    2. B.
      A lot of people died in this disaster.
    3. C.
      It cut off the electricity supply of the city.
    4. D.
      All of the above is right.
  4. 4.

    What can we learn from the text?

    1. A.
      President Bush was not concerned about this disaster.
    2. B.
      The recovery of the city will take a few days.
    3. C.
      In this disaster the government aid didn’t arrive in time.
    4. D.
      In this city there were no pump stations.

查看答案和解析>>

科目: 來源: 題型:閱讀理解

Between ten and midnight the United States is politically leaderless—there is no center of information anywhere in the nation except in the New York headquarters of the great broadcasting companies and two wire services. No candidate and no party can afford the investment on election night to match the news-gathering resources of the mass media; and so as every citizen sits in his home watching his TV set or listening to his radio, he is the equal of any other in knowledge. There is nothing that can be done in these hours, for no one can longer direct the great strike for America’s power; the polls have closed. Good or bad, whatever the decision, America will accept the decision—and cut down any man who goes against it, even though for millions the decision runs contrary to their own votes. The general vote is an expression of national will, the only substitute for violence and blood. Its decision is to be defended as one defends civilization itself.
There is nothing like this American expression of will in England or France, India or Russia. Only one other major nation in modern history has tried to elect its leader directly by mass, free, popular vote. This was the Weiman Republic of Germany, which modeled its unitary vote for national leaders on the American practice. Out of its experiment with the system it got Hitler. Americans have had Lincoln, Wilson and two Roosevelts. Nothing can be done when the voting returns are flooding in; the White House and its power will move to one or another of the two candidates, and all will know about it in the morning. But for these hours history stops.

  1. 1.

    Between ten P.M. and midnight the United States is politically leaderless because ________.

    1. A.
      the president has been murdered
    2. B.
      the general strike for power has ended
    3. C.
      the government has resigned
    4. D.
      the general vote is being held
  2. 2.

    “The great strike for America’s power” in Paragraph 1 refers to ________.

    1. A.
      the strike of the government members
    2. B.
      the great vote
    3. C.
      the election campaign
    4. D.
      the strike of the government employees
  3. 3.

    The author believes that the decision at the polls will ________.

    1. A.
      lead to a civil war
    2. B.
      result in a general strike
    3. C.
      cause violence and blood
    4. D.
      be defended by all Americans
  4. 4.

    Without the general vote, the author implies ________.

    1. A.
      there would be a civil war
    2. B.
      there would be a general strike
    3. C.
      there would be an election campaign
    4. D.
      there would be a fierce debate

查看答案和解析>>

科目: 來源: 題型:閱讀理解

To master a language one must be able to speak and understand the spoken language as well as to readand write. Lenin and his wife Krupskaya translated a long English book into Russian. But when theywent to England in 1902, English people couldn't understand what was said to them. These days more and more foreigners are coming to China and more Chinese are going out to foreign countries to work or study. So the spoken language is becoming more and more important.
Speaking, of course, can't go without listening. If you want to pronounce a word correctly, first you must hear it correctly. The sounds of the Chinese and English languages are not exactly the same. If you don't listen carefully, you'll find it difficult or even impossible to understand the native speakers.
Well, what about writing? Like speaking, it's to exchange ideas. People generally use shorter words and shorter sentences in their writing. The important thing is to make your idea clear in your head and then to write it in clear lively language.
Chinese students read far too slowly. If you read fast, you understand better. If you read too slowly, by the time you have reached the end of a page you have forgotten what the beginning is about. When you meet with new words, don't look them up in the dictionary. Guess the meaning from the context(上下文). You may not guess quite correctly the first time, but as new words come up again and again in different contexts, their meaning will become clearer and clearer. If you look up every word, you'll never finish a book.
Students of a foreign language need a particular knowledge, the knowledge of the life, history and geography of the people whose language they are studying. They should study these subjects in the
foreign language, not only in translation. In this way one can kill two birds with one stone: learn a foreign language and get some knowledge of the foreign country at the same time.

  1. 1.

    In the first paragraph, the writer told us _________.

    1. A.
      how to speak English well
    2. B.
      how to read and write English
    3. C.
      why spoken English is very important
    4. D.
      why English people couldn't understand Lenin
  2. 2.

    In order to study a foreign language, the writer thinks the best way is ______.

    1. A.
      to kill two birds with one stone
    2. B.
      to learn two languages at a time
    3. C.
      to study all the subjects in a foreign language
    4. D.
      to get some knowledge of the foreign country as well as learn the language
  3. 3.

    In the fourth paragraph the writer gave some advice on ____.

    1. A.
      how to imporve reading faster
    2. B.
      how to guess the meaning from the context
    3. C.
      how to look up new words in the dictionary
    4. D.
      how to grasp the general meaning of a passage
  4. 4.

    "To kill two birds with one stone" means ____.

    1. A.
      to get some particular knowledge
    2. B.
      to get more than what one pays
    3. C.
      the stone is too big
    4. D.
      the birds are blind enough

查看答案和解析>>

科目: 來源: 題型:閱讀理解

Several days ago, a Beijing-based IT com­pany fired about 400 people overnight. No one had expected the job cuts, which broke with traditional ways of letting go of workers in Chi­na. Moreover, what was special about this case was that the day before the 400 were fired, they all received from their boss a gift—the book “Who Moved My Cheese?”
The book—a bestseller in the US—is being used by men and women to deal with changes in their lives and work. Some large organizations, including Coca-Cola, Kodak and General Mo­tors, ask their employees to read it in order to encourage them to be active towards changes.
Cheese is something related to everyone’s livelihood—our jobs, the Industries we work in, relationships and love as well.  
With China’s official entry into the WTO, the whole nation will face more changes and cha­llenges. So what should we do once this “cheese” on which we are so dependent is moved?
whatever challenges and changes we meet, we should face up to them bravely, Jiang Hengwei, a civil servant said after reading the book.
Professor Zhang Yang in Renmin University of China agrees. “We should change our way of thinking. The coming competitive foreign com­panies and products provide us with great chances to learn from them and improve our own products to meet international standards and be more competitive.”
“With hard work and wisdom, we will create a much larger and better piece of cheese.” Zhang smiled confidently.            

  1. 1.

    The whole passage is about _______.

    1. A.
      people’s opinions about a bestseller of the US
    2. B.
      what people think about China’s entry into the WTO
    3. C.
      the change in people’s attitude towards changes and challenges
    4. D.
      how a book influences the Chinese
  2. 2.

    The company in Beijing gave each of the 400 fired workers a copy of “Who Moved My Cheese” in order to _______.

    1. A.
      be more competitive with foreign firms
    2. B.
      find an excuse for their job cuts
    3. C.
      let the workers make a living on their own
    4. D.
      encourage the fired workers
  3. 3.

    The word “cheese” in the passage can refer to _______.

    1. A.
      something we depend on for a living
    2. B.
      a most important kind of food
    3. C.
      change or challenge
    4. D.
      way of life
  4. 4.

    From what Hengwei and Professor Zhang Yang said, we can know that _______.

    1. A.
      they have different opinions on changes and challenges
    2. B.
      people are not afraid of competition from foreign companies
    3. C.
      the Chinese people are ready to face any changes and challenges
    4. D.
      they are both greatly encouraged by the book

查看答案和解析>>

科目: 來源: 題型:閱讀理解

In meditation(冥想),people sit quietly and focus their attention on their breath .As they breathe in and out ,they attend to their feelings .As thoughts go through their minds. They let them go. Breathe .Let go .Breathe .Let go .
According to a recent study at the Insight Meditation Society in Barre,Massachusetts. Three months of training in this kind of meditation causes a market change in how the brain allocates(分配) attention. It appears that the ability to let go thoughts that come into mind frees the brain to attend to more rapidly changing things and events in the outside world. Expert mediators are better than other people at catching such fast-changing stimuli( 刺激),like facial expressions.
The study provides evidence for changes in the workings of the brain with mental training. People can learn and improve abilities of all sorts with practice, everything from driving to playing the piano. The study has shown that meditation is good for the brain. It appears to reduce pressure and promote a sense of well-being.
In an experiment, 17 volunteers with no meditation experience in the experimental group spent three months meditating 10 to 12 hours a day .A control group also with no meditation experience meditated for 20 minutes a day over the same period .Both groups were then given the tests with two numbers in a group of letters. As both group looked for the numbers , their brain activity was recorded.
Everyone could catch the first number .But the brain recordings showed that the less experienced mediators tended to grasp the first number and hang onto it, so they missed the second number .Those with more experience gave less attention to the first number .as if letting it go ,which led to an increased ability to grasp the second number ,This shows that attention can change with practice.
Just ask Daniel Levision , who meditated for three months as part of the study .”I am a much better listener,” he said . “ I do not get lost in my own personal reaction to what people are saying.”

  1. 1.

    The underlined word “them” in Paragraph 1 refers to  __________  .

    1. A.
      feelings
    2. B.
      minds
    3. C.
      people
    4. D.
      thoughts
  2. 2.

      Meditations manage their daily tasks better because they   ________  .

    1. A.
      are given less pressure
    2. B.
      allocate their attention better
    3. C.
      have more stimuli for life
    4. D.
      practice them more frequently
  3. 3.

    In the experiment ,volunteers doing meditation for longer hours   _____  .

    1. A.
      were more likely to catch both of the members
    2. B.
      were used to memorizing numbers in groups
    3. C.
      usually ignored the first number observed
    4. D.
      paid more attention to numbers than to letters
  4. 4.

    The study proves that     _____ .

    1. A.
      meditation improves one’s health
    2. B.
      brain activity can be recorded
    3. C.
      human attention can be trained
    4. D.
      mediators have a good sense of hearing

查看答案和解析>>

同步練習(xí)冊答案