题目内容
Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
We all know that DNA has the ability to identify individuals but, because it is inherited, there are also regions of the DNA strand which can relate an individual to his or her family (immediate and extended) , tribal group and even an entire population. Molecular Genealogy (宗谱学) can use this unique identification provided by the genetic markers to link people together into family trees. Pedigrees (家谱) based on such genetic markers can mean a breakthrough for family trees where information is incomplete or missing due to adoption, illegitimacy(私生)or lack of records. There are many communities and populations which have lost precious records due to tragic events such as the fire in the Irish corms during Civil War in 1921 or American slaves for whom many records were never kept in the first place.
The main objective of the Molecular Genealogy Research Group is to build a database containing over 100,000 DNA samples from individuals all over the world. These individuals will have provided a pedigree(家谱) chart of at least four generations and a small blood sample. Once the database has enough samples to represent the world genetic make-up, it will eventually help in solving many issues regarding genealogies that could not be done by relying only on traditional written records. Theoretically, any individual will someday be able to trace his or her family origins through this database.
In the meantime, as the database is being created, molecular genealogy can already verify possible or suspected relationships between individuals. "For example, if two men sharing the same last name believe that they are related, but no written record 'proves this relationship, we can verify this possibility by collecting a sample of DNA from both and looking for common markers (in this ease we can look primarily at the Y chromosome (染色体))," explains Ugo A. Perego, a member of the BYU Molecular Genealogy research team.
People in a large area may possess the same DNA thread because？
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听力原文：W: I was in the gas station at 1:00. How did I miss you？
M: I got there a quarter past 12:00 and waited for a while, but I guess I left before you got there.
Q: When did the man most likely leave the gas station？
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听力原文：W: Do you have a savings account at the bank？
M: I used to, but recently I withdrew all the money.
Q: Which of the following statements is TRUE for the man's money？
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A．About 100 years ago.B．About 200 years ago.C．In Napoleon' s time.D．Quite recently.
Four Dangers to the Euro
Operating a single currency is not going to be easy. European economic and monetary union will not function without any difficulties. Indeed, signs of stress have already appeared. And these political, economic and social pressures will almost certainly intensify in the years to come. But EMU (经济贷币联盟) failure is a topic generally avoided in continental Europe. And for good reason the collapse of monetary union would almost certainly slam the European Union into political chaos and the world into financial crisis. "It would be almost as bad as a war in Europe," says Use Angenentdt, chief economist at BHF Bank in Frankfurt. The optimists contend EMU failure is not possible. They insist that the politicians will in Europe for monetary union be simply too strong to allow it to fail. But they overlook a simple fact: European politicians invented monetary union, and therefore they can destroy it. Some think the chances of EMU disintegration are highest before Euro notes and coins go into circulation Jan. 1, 2002. Others say, no, it would take more time for pressures to reach the explosive levels necessary to burst apart EMU. Whoever is right, here are a few of EMU' s weak points.
One Size Does Not Fit All
The prime requirement for EMU (one key interest rate for all 11 nations regardless of divergent economic cycles) is potentially its most dangerous fault line. The European Central Bank has said it will set its key interest rate at a level for average Euroland economic conditions.
You don' t have to be a chief economist to figure out that the fight key interest rate for the majority of Euroland, expected to grow at just over 2 percent next year, will not be right for Ireland, seen growing nearly 7 percent. The only way for Ireland to adjust would be through tough fiscal (财政的) tightening. An even bigger problem will come when most of Euroland is humming along with solid growth, but, say, Ireland and Portugal are sliding into recession after their booms have gone bust. The two nations would suffocate under the key interest rate and would not be able to devalue currencies as in the past. Fiscal stimulus also would be tricky because of the treaty that penalized countries who let their deficits(赤字) balloon.
Money to Burn
Another big fear is that Euroland nations, after years of fiscal penny saving to gain entry into EMU, will now go on wild spending. Some economists maintain that if only one or two nations overspend, peer pressure would quickly force them back to fiscal responsibility. The worst case would, be deficit spending by a majority of Euroland nations. And chances of this happening have grown after left-wing electoral victories in Germany and Italy, whose governments are now mare in line with the socialist government of France.
Many Germans did not want the Club Mediterranean nations of Italy, Portugal and Spain to be allowed into club Euro. The fear of Italy, with its large economy and history of huge deficits and political instability, was especially intense.
Adolf Rosenstock, economist at Nomura International in Frankfurt, thinks Italy could be the first nation to test EMU cohesiveness. "And this test might come sooner than we think. ", he warns.
The Politicians vs. the Bankers
While plenty of fault lines exist between nations, one huge crack is opening up between elected politicians and the bankers at ECB. Bad blood has already arisen between politicians and Euro central bankers. In response to the politicians' demands for rate cuts, central bankers have (in essence) told them to keep quiet and work instead of cutting structural deficits and reforming labor markets. Gabriel Stein, senior international economist at Lombard Street Research in London, says that a tight ECB monetary policy might prompt politicians to turn to deficit spending in o
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