Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It’s more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone’s origin.
Beneath the surface of a gemstone, on the tiny level of atoms and molecules, lie clues to its origin. At this year’s meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers to clarify these clues and identify a stone’s homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.
Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.
To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles called electrons separate from atoms.
The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.
In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.
Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News. We learn from Paragraph 1 that __________________.
| A．an emerald and a ruby are names of diamonds. |
| B．it’s not difficult to tell where the gem was mined. |
| C．appearances help to identify the origin of gemstones. |
| D．diamonds from different places may appear the same. |
Why did the U.S. government pass law that requires companies selling gemstones to determine the origins of their stones?
| A．To look for more gemstones. |
| B．To encourage violent civil wars. |
| C．To reduce the trade in blood minerals. |
| D．To develop the economy. |
Which of the following facts most probably helps McManus and her team in identifying the origin of stones?
| A．Heat can turn ice into water or water into steam. |
| B．Gemstones from the same area produce similar light patterns. |
| C．Laser can changes a miniscule part of the gemstone into plasma. |
| D．Materialytics has already collected patterns from thousands of gemstones. |
From the last two paragraphs, what can be inferred about the laser technique?
| A．It is ready for commercial use. |
| B．People can use the new tool to find more gemstones. |
| C．It can significantly reduce the gemstones trade in blood minerals. |
| D．It will bring about a revolutionary change in identifying the origin of minerals. |
The author wrote this passage mainly to ________.
| A．tell us how to identify the origin of diamonds. |
| B．introduce a laser technique in identifying a stone’s origin |
| C．prove identifying the origin of gemstones are difficult |
| D．attract our attention to reducing trade in blood minerals |
On Saturday, millions of people around the world will celebrate Saint Patrick’s Day, which honors Patron Saint (or main religious figure) of Ireland. Communities across the United States will host parades, parties, and other festivities to mark the occasion.
This year, cities like Boston, New York, and Chicago have organized massive events celebrating Saint Patrick’s Day. In New York City, hundreds of thousands of people will gather to watch the Saint Patrick’s Day parade—the nation’s largest. It is one of the most watched parades in the world. Last year, almost 2 million spectators（观众） and more than 150,000 participants （参与者）filled the streets. The parade, first held in 1776, is also one of the oldest.
Chicago also throws a big celebration. Every year, the Chicago River, which crosses the city, glows green as event organizers dump about 40 pounds of fluorescence, a powerful dye(染料), into the water.
Boston keeps its parade rolling for three hours or more. It is the nation’s second-largest parade. The city will also salute one of its most famous former residents, President John F. Kennedy, by opening the exhibit “A Journey Home: John F. Kennedy and Ireland,” at his official library.
Patron Saint lived in Britain in the early fifth century, when it was still part of the Roman Empire. He was captured （抓捕）and sold into slavery（卖为奴隶） in Ireland when he was only 16．He eventually escaped slavery and turned to a life of religious devotion. He trained to become a minister（牧师） and set out to spread Christianity throughout Ireland. After 30 years as a religious leader, Patrick died on March 17, 1461．Saint Patrick’s Day is always celebrated on March 17．In Ireland, it is an official holiday.
1．What’s the best title of the passage?
A．History of Saint Patrick’s Day B．An Official Holiday in US
C．The Largest Parade in the World D．Celebrations across the Country
2．What do you think is the official color of St. Patrick’s Day?
A．Green B．Red. C．Black. D．Yellow.
3．The last paragraph is mainly about _____.
A．the cruel slave trade. B．Saint Patrick’s contribution.
C．activities during Saint Patrick’s Day D．Ireland’s Patron Saint
4．Which of the following is not correct according to the passage?
A．Parade is a most important event to observe Saint Patrick’s Day.
B．Saint Patrick’s Day is a religious holiday.
C．Saluting the former president has become a main event on the occasion.
D．The Saint Patrick’s Day parade has a history of over two centuries.
A school in Nanjing plans to order Korean-style school uniforms (校服) for students, but parents were against the move, believing that the new uniforms looked too good and would encourage early romances among the students.
Parents: “My daughter was so excited about the Korean-style uniform, saying it’s her dream to wear a miniskirt to school every day,” a mom said. “My daughter also called her classmates to talk about how handsome the boys looked in the uniforms! If the students wear such beautiful uniforms, how can they concentrate on their studies?”School: We had to stop the plan because many parents were strongly against it. Some parents thought it was just a way for the school to make money, and others thought the new uniforms would take students’ attention away from their studies.Students: The students were very disappointed about the school’s final decision. They thought the sportswear uniforms made them look dull. They said the Korean uniforms had many advantages such as raising interest in class and lifting confidence.As for concerns about romance, the students believe that love is love and has no relationship to the uniforms.The Department of Education: The schools can choose their own styles. Either sportswear or other uniforms are OK. Currently, most middle and elementary schools in Nanjing have sportswear uniforms.Expert: Fashionable school uniforms can increase students’ interest in learning.Parents don’t need to worry too much about early romances. Today’s primary and middle school students have strong personalities and their appreciation of beauty is rapidly forming. A fashionable uniform can develop their sense of belonging to the school and reduce their resistance(反抗) to the school’s management.But we don’t have to follow Korean or Japanese styles. We should design our own Chinese style uniforms.
1．Students think the new uniforms will________. A. make them have good taste in fashion B. make them feel confident C. make them feel proud of their school D. reduce their fear of teachers
3．The opinion of the expert is to________. A. forbid the students to wear fashionable uniforms
B. encourage the students to wear sportswear uniforms
C. design uniforms in a Chinese style
D. wear new uniforms in a foreign style
3．We can infer from the passage that_________.
A. school uniforms are mostly blue or black
B. few students are willing to wear school uniforms C. school uniforms are a waste of money
D. schools are encouraged to choose their own uniforms
第三部分阅读理解（共15小题；每小题2分，满分30分）
请阅读下列短文,从每题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项的标号涂黑。
May 16th Wednesday Sunny
They used to call her “the witch（女巫）”, but today I found things were different.
My legs were too short to reach the floor from up there on the big chair. I was so afraid. My legs started to shake.
It was the first time I had been to the principal’s（校长的） office. And I knew what she was going to ask me.
Why had I been running on the concrete（混凝土） in the playground? Why hadn’t I followed the school rules?
The principal’s secretary was sitting at her desk. She kept asking me questions like whether I liked school and what grade I was in. I didn’t want to talk to her, so I just gave one-word answers.
Then she asked what my dad did. But I didn’t really know what he did, so I made something up. “He plays basketball for the Boston Celtics,” I said.
The secretary just looked at me, and said nothing more.
Just then, the door to the principal’s offic
e opened. There she was, the woman that everyone called “the witch”.
Was she really that bad? I was surprised to see her office walls were bright yellow, and there were some nice pictures on the desk.
She told me about the pictures. I was surprised that she had a family and a kid, just like me.
Then she asked how my family was. It turned out that she had known me since I was only a few weeks old. I was happy to hear that. If she knew my mum, then I wouldn’t get into much trouble.
She cleaned the cut on my knee and told me to be more careful. She also told me about the rules of the playground. But she didn’t punish or shout at me. And I forgot all the bad things I had heard about “the witch”. I had met her and I knew she was nice.
1．“The witch” in the story refers to _______.
A. the writer B. the writer’s father C. the secretary D. the principal
2．Which of the following statements is TRUE?
A. The writer often asked the principal for help.
B. The principal must be very strict with students.
C. Running in the playground was allowed by the school rules.
D. The writer’s father was an excellent basketball player.
3．Which word can replace the underlined phrase “made up” (in Paragraph 6)?
A. Told. B. Invented. C. Minded. D. Memorized.
4. How did the writer find the principal in the end?
A. Terrible. B. Kind. C. Proud. D. Strict.
A lot of us lose life's tough battles by starting a frontal attack--when a touch of humor might well enable us to win. Consider the case of a young friend of mine, who was on his trapped way to work shortly after receiving an ultimatum(最后通牒) about the job. Although there was a good reason for Sam's being late--serious illness at home--he decided that this by-now-familiar excuse wouldn't work any longer. His supervisor was probably already pacing up and down preparing a dismissal speech.
Yes, the boss was, Sam entered the office at 9:35. The place was as quiet as a locker room(更衣室); everyone was hard at work. Sam's supervisor came up to him. Suddenly, Sam forced a grin and stretched out his hand. "How do you do!" he said. "I'm Sam Maynard. I'm applying for a job, which, I understand, became available just 35 minutes ago. Does the early bird get the worm?"
The room exploded in laughter, except that the supervisor had to clamp off a smile and walked back to his office. Sam Maynard had saved his job--with the only tool that could win, a laugh.
Humor is a most effective, yet frequently neglected, means of handling the difficult situations in our lives. It can be used for patching up differences, apologizing, saying "no", criticizing, getting the other fellow to do what you want without his losing face. For some jobs, it's the only tool that can succeed. It is a way to discuss subjects so sensitive that serious dialog may start a quarrel. For example, many believe that comedians on television are doing more today for racial and religious tolerance than people in any other forum.
1. Why was Sam late for his job?
A. Because he was seriously ill at home. B. Because he received an ultimatum.
C. Because he was caught in a traffic jam. D. Because he was busy applying for a new job.
2. What is the main idea of this passage?
A. Sam Maynard saved his job with humor B. Humor is important in our lives
C. Early bird can get the worm D. Humor can solve racial discriminations
3. The phrase "clamp off" in Paragraph 3 means__________.
A. try to hold back B. pretend to set C. send off D. give out
4. Which of the following statements can we infer from the passage?
A. Many lose life's battles for they are lacking in a sense of humor.
B. It wasn't the first time that Sam came late for his work.
C. Sam was supposed to come to his office at 8:30.
D. Humor is the most effective way of solving problems.
With only about 1,000 pandas left in the world, China is desperately trying to clone the animal and save these in a dangerous situation. That's a move similar to what a Texas A & M University researchers have been undertaking for the past five years in a project called "Noah's Ark".
Noah's Ark is aimed at collecting eggs, embryos(胚胎), semen and DNA of these animals and storing them in liquid nitrogen. If certain species should become extinct, Dr. Duane Kraemer, a professor in Texas A & M's College of Veterinary, Medicine, says there would be enough of the basic building blocks to reintroduce the species in the future.
It is estimated that as many as 2, 000 species of mammals, birds and reptiles will probably become extinct in over 100 years. The panda, native only to China, is in danger of becoming extinct in the next 25 years.
This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal.
The entire procedure could take from three to five years to complete.
"The nuclear transfer of one species to another is not easy, and the lack of available panda eggs could be a major problem," Kraemer believes. "They will probably have to do several hundred transfers to result in one pregnancy (having a baby). It takes a long time and it's difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort," adds Kraemer, who is one of the leaders of the Project at Texas A& M, the first-ever attempt at cloning a dog.
"They are trying to do something that's never been done, and this is very similar to our work in Noah's Ark. We're both trying to save animals that face extinction. I certainly appreciate their effort and there's a lot we can learn from what they are attempting to do. The cooperation between us is very much needed."
1. The aim of "Noah's Ark" project is to__________.
A. make efforts to clone the endangered pandas
B. save endangered animals from dying out
C. collect DNA of endangered animals to study
D. transfer the nuclear of one animal to another
2. According to Professor Kraemer, __________.
A. The long time lasting cloning research could be successful.
B. The eggs transfers immediately result in having a baby.
C. The lack of nuclear transfer could be a major problem to have new pandas.
D. If species should die out, basic building blocks would heal them.
3. The best title for the passage may be__________.
A. China's Success in Pandas Cloning
B. Helping Ways to Avoid Extinction
C. Exploring the Possibility to Clone Pandas
D. The Practice in Noah's Ark
4. From the passage we know that __________.
A. Kraemer and his team have succeeded in cloning a dog
B. scientists try to implant a panda's egg into a rabbit
C. about two thousand of species are to die out in a century
D. Kraemer will work with Chinese scientists in clone researches
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