Most people know precious gemstones (寶石) 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（分子）, lie clues (線索) 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 (激光) 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（微粒）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（元素）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.
小題1:We learn from Paragraph 1 that __________________.
A．a(chǎn)n emerald and a ruby are names of diamonds.
B．it’s not difficult to tell where the gem was mined.
C．a(chǎn)ppearances help to identify the origin of gemstones.
D．diamonds from different places may appear the same.
小題2: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.
小題3: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.
小題4: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.
小題5: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．a(chǎn)ttract our attention to reducing trade in blood minerals

小題1:D
小題2:C
小題3:B
小題4:D
小題5:B

試題分析：來(lái)自不同地方的鉆石可能看起來(lái)是一樣的，如何識(shí)別寶石的家？這篇文章主要是介紹一種使用激光技術(shù)識(shí)別寶石來(lái)源的方法。
小題1:細(xì)節(jié)題：從文章第一段的句子：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.可知來(lái)自不同地方的鉆石可能看起來(lái)是一樣的，選D
小題2:細(xì)節(jié)題：從文章第三段的句子：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.可知為什么美國(guó)政府要求出售寶石的公司確定寶石的來(lái)源，是為了減少血礦石的交易。選C
小題3:細(xì)節(jié)題：從文章第五段的句子：but McManus and her team say that gemstones from the same area produce similar patterns.可知最能夠幫助McManus和她的團(tuán)隊(duì)識(shí)別石頭的來(lái)源的是來(lái)自同樣地區(qū)的寶石有相似的光譜，選 B
小題4:細(xì)節(jié)題：從文章最后兩段的句子：In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. 和“This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.可知激光技術(shù)將在識(shí)別礦物質(zhì)的來(lái)源中帶來(lái)革命性的改變，選D
小題5:寫作意圖題：從文章第二段的句子：At this year’s meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone’s homeland.可知作者寫這篇文章主要是介紹一種使用激光技術(shù)識(shí)別寶石來(lái)源的方法。選B
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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

Businesses are witnessing a difficult time，which has in turn produced influence on consumers’ desire to go green.However，shoppers are still laying stress on environmental concerns.
Two thirds of customers say that environmental considerations inform their purchases to the same degree as they did a year ago，while more than a quarter say that they are now even better aware of the environmental effect on what they buy.
This may help to influence how shops store goods on their shelves.And the companies should still make efforts to become more environmentally friendly.Two out of three people think it is important to buy from environmentally responsible companies，with about one in seven saying that they had even decided to take their custom elsewhere if they felt a company’s environmental reputation was not good enough.
Harry Morrison，chief executive(主管)of the Carbon Trust，sympathizes：“I understand this situation where survival is very important now.But from environmental considerations，the clock is ticking—we don’t have much time.In addition，cutting carbon has an immediate effect as costs drop and a medium­term benefit for the brand.”
Larger companies have an extra motivation to look at reducing their carbon footprint，as new rules next year will require businesses to buy carbon allowances to make up for their emissions(排放)．Those that have taken early action will have a head start.More than two thirds of consumers are not clear about which companies are environmentally responsible.This suggests that firms that are able to relay clearly their message to the public will be in a pole position to attract shoppers.
The Carbon Trust believes that it can help by informing customers about the good work companies are doing.“When companies are granted(授予) the standard，they can use a logo(標(biāo)識(shí)) in all their marketing which makes it clear that they are working towards cutting emissions，” Mr.Morrison said.                                                  (2010·福建，C)
小題1:What’s the main idea of the passage?
A．Businesses are finding ways to send their message to the shoppers.
B．Companies will soon get information about cutting carbon emissions.
C．Firms are making efforts to encourage customers to keep goods at home.
D．Firms are urged to cut carbon emissions by shoppers’ environmental awareness.
小題2:The underlined word “inform” in Paragraph 2 probably means “________”．
A．a(chǎn)ffectB．changeC．disturbD．reject
小題3:According to Harry Morrison，businesses ________.
A．will benefit from cutting carbon emissions
B．should buy carbon allowances for shoppers
C．a(chǎn)re required to make up for their carbon emissions
D．have encouraged shoppers to take their custom elsewhere
小題4:We can learn from the passage that businesses will________.
A．have a strong desire to reduce costs
B．use the same logo in their marketing
C．gain advantages by taking early action
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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

(2013·高考新課標(biāo)全國(guó)卷Ⅱ，C)Given that many people’s moods (情緒)are regulated by the chemical action of chocolate，it was probably only a matter of time before somebody made the chocolate shop similar to a drugstore of Chinese medicine.Looking like a setting from the film Charlie&the Chocolate Factory，Singapore’s Chocolate Research Facility (CRF) has over 100 varieties of chocolates.Its founder is Chris Lee who grew up at his parents’ corner store with one hand almost always in the jar of sweets.
If the CRF seems to be a smart idea，that’s because Lee is not merely a seasoned salesperson but also head of a marketing department that has business relations with big names such as Levi’s and Sony.That idea surely results in the imagination at work when it comes to making different flavored (味道) chocolates.
The CRF’s produce is “green ”，made within the country and divided into 10 lines，with the Alcohol Series being the most popular.The Exotic Series－with Sichuan pepper，red bean (豆)，cheese and other flavors－also does well and is fun to taste.And for chocolate_snobs，who think that they have a better knowledge of chocolate than others，the Connoisseur Series uses cocoa beans from Togo，Cuba，Venezuela，and Ghana，among others.
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A．It serves as a suitable gift.
B．It works as an effective medicine.
C．It helps improve the state of mind.
D．It strengthens business relations.
小題2:Why is Chris Lee able to develop his idea of the CRF?
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B．He learns from shops of similar types.
C．He has the support of many big names
D．He has a lot of marketing experience.
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B．The Exotic Series.
C．The Alcohol Series.
D．The Sichuan Series.
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A．a(chǎn)re particular about chocolate
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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

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What if Timothy spent thirteen hours a day at a sewing machine instead of a desk? We would immediately be shocked, because that would be called children being horribly mistreated. Timothy was far from being mistreated, but the mountain of homework he faced daily resulted in a similar consequence — he was being robbed of his childhood. In fact, Timothy had no time to do anything he truly enjoyed, such as playing video games, watching movies, or playing board games with his friends.
Play, however, is a crucial part of healthy child development. It affects children’s creativity, their social skills, and even their brain development. The absence of play, physical exercise, and free­from social interaction takes a serious toll on many children. It can also cause significant health problems like childhood obesity, sleep problems and depression.
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小題1:What did the writer think of Timothy after learning about his typical day__________?
A．Timothy was very hard­working.
B．Timothy was being mistreated.
C．Timothy had a heavy burden.
D．Timothy was enjoying his childhood.
小題2:Which of the following statements best describes the writer’s opinion________?
A．Children should be allowed enough time to play.
B．Playing board games works better than playing video games.
C．The more they play, the more creative children will become.
D．The depression caused by homework makes children unwilling to play.
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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

Researchers conducting a study of hospital stays for over two hundred and eighty six thousand older folks found something interesting in their data.
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A．got flu shots after they were ill
B．got flu shots before they were ill
C．got flu shots at the flu season
D．got flu shots whenever convenient
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A．it can cut down on the chances of getting pneumonia
B．it can cut down the number of hospitalizations for heart disease
C．it can kill the flu virus
D．if can make blood clots
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Way back in 1662，John Evelyn，a brilliant Englishman known for his detailed diaries，wrote about disastrous effects of coal-burning on the city of London .In it,he described an infernal scene of smog．a(chǎn)ir filled with “Columns and Clouds of Smoke’’given out by small industries and residences that burned coal for fuel．
I found the description in the 2003 book When Smoke Ran like Water，by epidemiologist(流行病學(xué)家)and environmental advocator(倡導(dǎo)者)Devra Davis．In it,Davis looks back at several historic pollution events and their disastrous effect on human human health-and at how these phenomena were often Ignored or even actively covered up by then people in charge at that time.
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not pan out．
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小題1:The passage is written to     
A．warn people of the danger from air pollution
B．introduce London’s Great Smog of l952
C．blame the government for the smog
D．explain the reasons for air pollution
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A．imaginaryB．a(chǎn)dventurousC．unbelievableD．a(chǎn)nnoying
小題3:One of the reasons for the Great Smog of l952wasthat——
A．people burned wood for fuel
B．a(chǎn) forest fire created a black cloud over the city
C．the government ignored the smog
D．most people went abouttheirbusine00
小題4:How does the writer feel about the present air condition in London?
A. lndifferent   B Concerned    C．Hopeless．D. Panic

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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

Redwood trees are the tallest plants on the earth，reaching heights of up to 100 meters．They are also known for their longevity，typically 500 to 1000 years，but sometimes more than 2000 years．A hundred million years ago，in the age of dinosaurs，redwoods were common in the forests of a much more moist and tropical North America．As the climate became drier and colder，they declined to a narrow strip along the Pacific coast of Northern Califomia．
The trunk of redwood trees is very strong and usually forms a single straight column．It is covered with a soft bark．This bark can be pretty thick，well over two feet in the more mature trees．It gives the older trees a certain kind of protection from insects，but the main benefit is that it keeps the center of the tree harmless from moderate forest fires because of its thickness．This fire resistant quality explains why the giant redwood grows to live that long．While most other types of trees are destroyed by forest fires，the giant redwood actually prospers because of them．
Moderate fires will clear the ground of competing plant life，and the rising heat dries and opens the ripe fruit of the redwood，releasing many thousands of seeds onto the ground below．
New trees are often produced from shoots，little baby trees，which form at the base of the trunk．These shoots grow slowly，fed by the root system of the “mother’’ tree．When the main tree dies，the shoots are then free to grow as full trees，forming a “fairy ring” of trees around the original tree．These trees，in turn，may give rise to more shoots，and the cycle continues．
小題1:Why were redwood trees easier to find in the forests of North America millions of years ago?
A．The trees were taller and stronger．
B．The soil was softer for seeds to develop．
C．The climate there was warmer and wetter．
D．The temperature was lower along the Pacific coast．
小題2:Which of the following is a function of the tree bark as mentioned in the passage?
A．It allows redwood trees to bear seeds．
B．It prevents redwood trees from attack by insects．
C．It helps redwood trees absorb water in the air．
D．It makes redwood trees more beautiful and appealing．
小題3:Why do redwood trees grow to live that long according to the passage?
A．They have heavy and straight tree trunks．
B．They are properly watered and catered to．
C．They are more resistant to fire damage than other trees．
D．They produce many young trees to maintain their life cycle．
小題4:How does a “fairy ring’’ form according to the passage?
A．By killing an old tree．B．By connecting root systems．
C．By inserting holes into old trees．D．By surrounding a mature tree．

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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

Although websites such as Facebook and MySpace experienced rapid growth during the middle of the first decade of the 21st century, some users remain unaware of the fact that the information they post online can come back to haunt them. First, employers can monitor employees who maintain a blog, photo diary, or website. Employers can look for controversial(引起爭(zhēng)議的) employee opinions, sensitive information disclosures, or wildly inappropriate conduct. For example, a North Carolina newspaper fired one of its features writers after she created a blog on which she wrote about the strange things of her job and coworkers without signing her real name.
The second unintended use of information from social networking websites is employers who check on prospective employees. A June 11, 2006 New York Times article reported that many companies use search engines and social networking websites such as MySpace, Xanga, and Facebook to conduct background checks on college campuses. Although the use of MySpace or Google to check a student’s background is somewhat unsettling to many undergraduates, the Times noted that the use of Facebook is especially shocking to students who believe that Facebook is limited to current students and recent alum(校友).
Corporate employers are not the only people interested in college students’ lives. The third unintended use of social networking websites is college administrators who monitor the Internet — especially Facebook — for student bad behavior. For example, a college in Boston’s Back Bay expelled (除名) its student Government Association President for joining a Facebook group highly critical of a campus police sergeant. In addition, fifteen students at a state university in North Carolina faced charges in court for underage drinking because of photos that appeared on Facebook.
Although more users of websites such as Facebook are becoming aware of the potential dangers of online identities, many regular users still fail to take there basic security precautions(警惕). First, only make your information available to a specific list of individuals whom you approve. Second , regularly search for potentially harmful information about yourself that may have been posted by mistake or by a disgruntled
(不滿的)former associate. Thrid, never post obviously offensive material will likely make its way to the wider world. By taking these simple steps, members of the digital world can realize the many benefits of e-community without experiencing some of the damaging unintended consequences.
小題1:The main purpose of the passage is to _____.
A．explain the growth of the digital world from the view of privacy
B．discuss the risks of the digital world and suggest ways to protect yourself
C．propose steps Facebook, MySpace and Google can take to protect user privacy
D．illustrate(說(shuō)明) potential unintended uses of private information
小題2:The writer implies that users should take all of the following actions to protect their online privacy EXCEPT _____.
A．know to whom you make your online information available
B．a(chǎn)ctively hunt for damaging information posted about you or under your name
C．speak with employers to inform them of any misinformation published about you
D．a(chǎn)void uploading information that would be extremely damaging if it were discovered
小題3:According to the passage, which of the following does the author imply?
A．Information obtained unwillingly from the Internet is permitted in court.
B．It is impossible to protect yourself from unintended uses of information online.
C．Even if you restrict who can view your data, the government may still access it.
D．Done properly, posting offensive information about oneself brings no risk.
小題4:In the last paragraph the author mainly _____.
A．offers detailed examples to support previous viewpoints
B．further explores the ill-effects of the Internet on the protection of privacy
C．summarizes the points of the above paragraphs
D．provides suggestions to overcome the previously mentioned problems

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科目：高中英語(yǔ) 來(lái)源：不詳 題型：閱讀理解

Recently we told you about a finding that more years of school could help students get higherscores on intelligence tests．That was the finding of a study of teenage males in Norway．Now，other research shows that physical activity may help students do better in their classes .
The research comes as educators in some countries are reducing time for activities like physical education．They are using the time instead for academic subjects like maths and reading．The studies appeared between 2007 and 2013．They included more than 55，000 children，aged 6 to 18．
Amika Singh：“Based on the results of our study，we can conclude that being physically active is beneficial for academic performance. There are，first，Physiological explanations，like more blood flow, and so more oxygen to the brain．Being physically active means there are more hormones(荷爾蒙)produced like endorphins(內(nèi)啡肽)．And endorphins make your stress level lower and  your mood improved, which means you also perform better.”
Also，students involved in organized sports learn rules and how to follow them．This could improve their classroom behavior and help them keep their mind on their work．
The study leaves some questions unanswered，however．Ms．Stash says it is not possible to say whether the amount or kind of activity affected the level of academic improvement．This is because of differences among the studies .
Also．they were mostly observational studies．An observational study is where researchers do not do controlled comparisons．They only describe what they observe．So they might observe a link that students who are more active often have better grades．But that does not necessarily mean being active was the cause of those higher grades．
The researchers said they found only two high - quality studies．They called for more high-
quality studies to confirm their findings．They also pointed out that “outcomes for other parts of the world may be quite different. ”
Still，the general finding was that physically active kids are more likely to do better in school．Ms．Singh says schools should consider that finding before they cut physical education programs．Her paper on “Physical Activity and Performance at School”is published in the Archives of Pediatric and Adolescent Medicine．
小題1:The passage mainly tells us that ＿＿＿＿
A．a(chǎn) research on physical education has been done by the researchers
B．there exists a possibility that physical activity leads to higher grades
C．the amount or kind of activity directly affects academic level
D．the research shows that the children aged 6 to 1 8 don't do sports
小題2:Which of the following is TRUE?
A．Being mentally active is good for academic subjects．
B．The more hormones you have，the more stressed you will get．
C．They have found many high-quality studies to prove the research．
D．The educators in the research think studies，not exercise，mean much to students．
小題3:The underlined sentence in Paragraph 7 probably means ＿＿＿＿.
A．good marks result from high-quality study
B．findings probably vary in different areas
C．physical activity will spread all over the world
D．a(chǎn)cademic performance depends on the surroundings
小題4:What's the purpose of writing the passage?
A．To call our attention to the sports at school．
B．To introduce all types of physical activities．
C．To represent the academic performance．
D．To improve students' health ．

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