文章大意：第一段先说珍珠在古代是富贵和地位的象征，在古罗马是怎么样的，在波斯被当做是可以医治百病的药。第二段说pearl的分类，natural和cultural。第三段说natural pearl的培育分为盐水培育和淡水培育。盐水培育一般质量比较高，淡水培育中有部分质量比较高。第四段写natural pearl的很多特点。第五段写natural pearl和cultural pearl的区别。natural pearl的form和很多因素有关，说明natural pearl很难得到，而cultural pearl就容易很多。第六段写几种pearl没有经过训练，肉眼是分不出来的。只有在X光下才能出来。然后说pearl的价值与size和光泽度有关。第七段说日本的珍珠是世界上最贵的珍珠之一
The Pearl
A
Throughout history, pearls have held aunique presence within the wealthy and powerful. For instance, the pearl wasthe favored gem of the wealthy during the Roman Empire. This gift from the seahad been brought back from the orient by the Roman conquests. Roman women worepearls to bed so they could be reminded of their wealth immediately upon wakingup. Before jewelers learned to cut gems, the pearl was of greater value thanthe diamond. In the Orient and Persia Empire, pearls were ground into powdersto cure anything from heart disease to epilepsy, with possible aphrodisiac usesas well. Pearls were once considered an exclusive privilege for royalty. A lawin 1612 drawn up by the Duke of Saxony prohibited the wearing of pearls bynobility,professors, doctors or their wives in an effort to further distinguishroyal appearance. American Indians also used freshwater pearls from theMississippiRiver as decorations and jewelry.
B
There are essentially three types ofpearls: natural, cultured and imitation. A natural pearl (often called anOriental pearl) forms when an irritant, such as a piece of sand, works its wayinto a particular species of oyster, mussel, or clam. As a defense mechanism,the mollusk secretes a fluid to coat the irritant.Layer upon layer of thiscoating is deposited on the irritant until a lustrouspearl is formed.
C
The only difference natural pearls andcultured pearls is that the irritant is a surgically implanted bead or piece ofshell called Mother of Pearl. Often, these shells are ground oyster shells thatare worth significant amounts of money in their own right as irritant-catalystsfor quality pearls. The resulting core is, much larger than in a natural pearl.Yet, as long as there are enough layers of nacre (the secreted fluid coveringthe irritant) to result in a beautiful, gem-quality pearl, the size of thenucleus is of no consequence to beauty or durability.
D
Pearls can come from either salt orfreshwater sources. Typically, saltwater pearls tend to be higher quality,although there are several types of freshwater pearls that are considered highin quality as well. Freshwater pearls tend to be very irregular in shape, witha puffed rice appearance the most prevalent. Nevertheless, it is eachindividual pearls merits that determines value more than the source of thepearl. Saltwater pearl oysters are usually cultivated in protected lagoons orvolcanic atolls. However, most freshwater cultured pearls sold today come fromChina. Cultured pearls are the response of the shell to a tissue implant. Atiny piece of mantle tissue from a donor shell is transplanted into a recipientshell. This graft will form a pearl sac and the tissue will precipitate calciumcarbonate into this pocket. There are a number of options for producingcultured pearls: use freshwater or seawater shells, transplant the graft intothe mantle or into the gonad, add a spherical bead or do it nonbeaded. Themajority of saltwater cultured pearls are grown with beads.
E
Regardless of the method used to acquirea pearl, the process usually takes several years. Mussels must reach a matureage, which can take up t0 3 years, and then be implanted or naturally receivean irritant. Once the irritant is in place, it can take up to another 3 yearsfor the pearl to reach its full size. Often, the irritant may be rejected, thepearl will be terrifically misshapen, or the oyster may simply die from diseaseor countless other complications. By the end of a 5 t0 10 year cycle, only 50%of the oysters will have survived. And of the pearls produced, onlyapproximately 5% are of substantial quality for top jewelry makers. From theoutset, a pearl fanner can figure on spending over $100 for every oyster thatis farmed, of which many will produce nothing or die.
F
Imitation pearls are a different story altogether.In most cases, a glass bead is dipped into a solution made from fish scales.This coating is thin and may eventually wear off. One can usually tell animitation by biting on it. Fake pearls glide across your teeth, while the
layers of nacre on real pearls feelgritty. The Island of Mallorca (in Spain) is known for its imitation pearlindustry. Quality natural pearls are very rare jewels. The actual value of anatural pearl is determined in the same way as it would be for other “precious” gems.
The valuation factors include size,shape, color, quality of surface, orient and luster. In general, culturedpearls are less valuable than natural pearls, whereas imitation pearls almosthave no value. One way that jewelers can determine whether a pearl is culturedor natural is to have a gem lab perform an x-ray of the pearl. If the x-rayreveals a nucleus, the pearl is likely a beadnucleated saltwater pearl. If nonucleus is present, but irregular and small dark inner spots indicating acavity are visible, combined with concentric rings of organic substance, thepearl is likely a cultured freshwater. Cultured freshwater pearls can often beconfused for natural pearls which present as homogeneous pictures whichcontinuously darken toward the surface of the pearl. Natural pearls will oftenshow larger cavities where organic matter has dried out and decomposed.Although imitation pearls look the part, they do not have the same weight orsmoothness as real pearls, and their luster will also dim greatly. Amongcultured pearls, Akoya pearls from Japan are some of the most lustrous. A goodquality necklace of 40 Akoya pearls measuring 7mm in diameter sells for about$1,500, while a super- high quality strand sells for about $4,500. Size on theother hand, has to do with the age of the oyster that created the pearl (the moremature oysters produce larger pearls) and the location in which the pearl wascultured. The South Sea waters of Australia tend to produce the larger pearls;probably because the water along the coast line is supplied with rich nutrientsfrom the ocean floor. Also, the type of mussel common to the areaseems topossess a predilection for producing comparatively large pearls.
G
Historically, the world’s best pearls came from the PersianGulf, especially around what is now Bahrain. The pearls of the Persian Gulfwere natural created and collected by breath-hold divers. The secret to the specialluster of Gulf pearls probably derived from the unique mixture of sweet andsalt water around the island. Unfortunately, the natural pearl industry of thePersian Gulf ended abruptly in the early 1930’s with the discovery of largedeposits of oil. Those who once dove for pearls sought prosperity in theeconomic boom ushered in by the oil industry. The water pollution resultingfrom spilled oil and indiscriminate over-fishing of oysters essentially ruinedthe once pristine pearl producing waters of the Gulf. Today, pearl diving ispracticed only as a hobby. Still, Bahrain remains one of the foremost tradingcenters for high quality pearls. In fact, cultured pearls are banned from theBahrain pearl market, in an effort to preserve the location’s heritage. Nowadays, the largest stockof natural pearls probably resides in India. Ironically, much of India’s stock of natural pearls cameoriginally from Bahrain. Unlike Bahrain, which has essentially lost its pearlresource, traditional pearl fishing is still practiced on a small scale inIndia.
答案：
1.B 2.D 3.E 4.E 5.TRUE 6.FALSE
7.NOT GIVEN 8.B 9.J 10.K 11.F 12.C 13.D
Passage2：欧洲热浪 Europe heat wave
2003 年 6 月以来，欧洲许多国家和地区持续炎热和干旱，意大利气温比以往同期高出 6-10 度；瑞士气温创 200年来最高，意大利北部/法国南部地区遭受了50 年甚至百年以来的重大旱灾。高温干旱致使河流、水位下降、航运受阻、农作物面临减产等，损失严重，虽然各地出现异常高温的具体原因不尽相同，但总体上看应与全球变暖有一定关系。
European Heat Wave
A It was the summer, scientists now realize, when felt. We knew that summer2003 was remarkable: global warming at last made itself unmistakably Britain experiencedits record high temperature and continental Europe saw forest fires raging outof control, great rivers drying of a trickle and thousands of heat relateddeaths. But just how remarkable is only now becoming clean.
B The three monthsof June, July and August were the warmest ever recorded in western and centralEurope, with record national highs in Portugal, Germany and Switzerland as wellas Britain. And they were the warmest by a very long way Over a greatrectangular block of the earth stretching from west of Paris to northern Italy,taking in Switzerland and southern Germany, the average temperature for thesummer months was 3.78℃ above the long-term norm, said theClimatic Research Unit (CRU) of the University of East Anglia in Norwich, whichis one of the world’s lending institutions for the monitoringand analysis of temperature records.
C That excessmight not seem a lot until you are aware of the context-but then you realise itis enormous. There is nothing like this in previous data, anywhere. It isconsidered so exceptional that Professor Phil Jones, the CRU’s director, is prepared to say openly-in a way fewscientists have done before that the 2003 extreme may be directly attributed,not to natural climate variability, but to global warming caused by humanactions.
D Meteorologistshave hitherto contented themselves with the formula that recent hightemperatures are consistent with predictions” ofclimate change. For the great block of the map-that stretching between 35-50Nand 0-20E-the CRU has reliable temperature records dating back to 1781. Usingas a baseline the average summer temperature recorded between 1961 andl990,departures from the temperature norm, or “anomalies’: over the area as a whole can easily be plotted. Asthe graph shows, such is the variability of our climate that over the past 200years, there have been at least half a dozen anomalies, in terms of excesstemperature-the peaks on the graph denoting very hot years approaching, or evenexceeding, 20 ℃ . But there has been nothing remotely like2003， when the anomaly is nearly four degrees.
E “This is quite remarkable,” Professor Jones told The Independent. “It’s very unusual in a statistical sense. Ifthis series had a normal statistical distribution, you wouldn’t get this number. There turn period “how often it could be expected to recur” would be something like one in a thou-sand years. Ifwe look at an excess above the average of nearly four degrees, then perhaps
nearly three degrees of that is natural variability, because we’ve seen that in past summers. But the final degree ofit is likely to be due to global warming, caused by human actions.
F The summer of2003 has, in a sense, been one that climate scientists have long beenexpecting. Until now, the warming has been manifesting itself mainly in wintersthat have been less cold than in summers that have been much hotter. Last week,the United Nations predicted that winters were warming so quickly that wintersports would die out in Europe’s lower-level ski resorts. But sooner orlater the unprecedented hot summer was bound to come, and this year it did.
G One of the mostdramatic features of the summer was the hot nights, especially in the firsthalf of August. In Paris, the temperature never dropped below 230 ℃ (73.40 ℉ ) at allbetween 7 and 14August, and the city recorded its warmest-ever night on 11-12August, when the mercury did not drop below 25.50 ℃ (77.90 ℉ ).Germany recorded its warmest-ever night at Weinbiet in the Rhine valley with alowest figure of 27.60℃ (80.60 ℉ ) on 13August, and similar record-breaking nighttime temperatures were recorded inSwitzerland and Italy.
H The 15,000excess deaths in France during August, compared with previous years, have beenrelated to the high night-time temperatures. The number gradually increasedduring the first 12days of the month, peaking at about 2,000 per day on thenight of 12-13 August, then fell off dramatically after 14 August when theminimum temperatures fell by about 50C. The elderly were most affected, with a70 per cent increase in mortality rate in those aged 75-94.
I For Britain, theyear as a whole is likely to be the warmest ever recorded, but despite the hightemperature record on 10 August, the summer itself defined as he June, July andAugust period-still comes behind 1976 and 1995, when there were longer periodsof intense heat. At the moment, the year is on course to be the third-hottestever in the global temperature record， whichgoes back to 1856, behind 1998 and 2002 but when all the records for October,November and December are collated, it might move into second place, ProfessorJones said. The 10 hottest years in the record have all now occurred since1990. Professor Jones is in no doubt about the astonishing nature of European summerof 2003.”The temperatures recorded were out of all
proportion to the previous record,” he said. “It was the warmest summer in the past 500 years andprobably way beyond that It was enormously exceptional.”
J His colleaguesat the University of East Anglia’s TyndallCentre for Climate Change Research are now planning a special study of it. “It was a summer that has not: been experienced before,either in terms of the temperature extremes that were reached, or the range anddiversity of the impacts of the extreme heat,” said thecentre’s executive director, Professor Mike Hulme.“It will certainly have left its mark on a number ofcountries, as to how they think and plan for climate change in the future, muchas the 2000 floods have revolutionised the way the Government is thinking aboutflooding in the UK.“ The 2003 heat wave will have similarrepercussions across Europe.”
Questions 14-19
Do the following statements agree with the information given in Reading
Passage 2?
In boxes 14-19 on your answer sheet, write T/F/NG
14 The average summer temperature in 2003 is approximately four degrees higher than that of the past.
15 Jones believes the temperature statistic is within the normal range.
16 Human factor is one of the reasons that caused hot summer.
17 In large city, people usually measure temperature twice a day.
18 Global warming has obvious effect of warmer winter instead of hotter summer before 2003.
19 New ski resorts are to be built on a high-altitude spot.
Questions 20-21
Answer the questions below using NO MORE THAN THREE WORDS AND/OR NUMBERS from the passage for each answer. Write your answers inboxes 20-21 on your answer sheet.
20 What are the two hottest years in Britain besides 2003?
21 What will affect UK government policies besides climate change according to Hulme?
Questions 22-26
Complete the summary below using NO MORE THAN TWO WORDS from the passage. Write your answers in boxes 22-26 On your answer sheet.In the summer of 2003, thousands of extra death occurred in the country of 22………… . Moreover, world-widely, the thirdrecord of hottest summer date from 23……………. , after the year of 24………… . According to Jones, all the
10 hottest years happened from 25………… .However, summer of 2003 was at the peak of previous 26…………. years, perhaps even more.
Question 27
Choose the correct letter A, B, C or D
Write your answer in box 27 on your answer sheet
27 Which one can be best served as the title of this passage in the following
options?
A Global Warming effect
B Global Warming in Europe
C The Effects of hot temperature
D Hottest summer in Europe
答案：
14 True
15 False
16 True
17 Not given
18 True
19 Not given
20 1976 and 1995
21 2000 floods
22 France
23 1856
24 1998 and 2002
25 1990
26 500
27 D
Passage3：当代科学
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