The comparison of the old and new flu viruses is the first practical use of a science use of a science-fiction-like scenario that concluded yesterday with the release of two papers, one by the journal Science and the other by its chief competitor, Nature.

　　After 10 years of work, Taubenberger and his team succeeded in reconstructing the Spanish flu virus, which was responsible for the deadliest epidemic since the Black Death of the Middle Ages. Reborn in the mid-August at a high-security laboratory at the Centers for Disease Control and Prevention in Atlanta, the pathogen appears in animal experiments to be as lethal as it was in human 87 years ago.

　　The report came as the United States, many other countries and the World Health Organizatiom are making increasingly urgent preparations for a new flu pandemic. The Department of Health and Human Services is stockpiling antiviral drugs and is buying enough experimental bird flu vaccine to inoculate 20 million people. President Bush ( the former president of America ) said in a news conference this week that he is considering the use of the military to enforce quarantines, if necessary, and that the government’s long-awaited pandemic plan will be released soon.

　　What makes the accomplishment reported yesterday so remarkable is that no intact samples of the Spanish flu virus exist. When the pandemic occurred in 1918 and early 1919— only American Samoa and parts of Iceland appear to have been spared— microbiologists did not know for certain what caused it. ( The influenza virus was not identified until 1933.) Although biologists were later able to deduce the broad family of influenza viruses the 1918 strain came from, its genetic identity was lost.

　　注意：此部分試題請在答題卡2上作答。

　　47.How important it is to find the similarities between the 1918 Spanish flu virus and the Asian avian influenza virus ?

　　48.What journals published two papers comparing the two viruses ?

　　49.After Taubenberger and his colleagues worked 10 years, the great success they have achieved is that _________________.

　　50.As part of the official preparations for bird flu, the U.S. government will soon ____________.

　　51.During and after World War Ⅰ，the whole world was affected by the pandemic except_________.

　　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 and mark the corresponding letter on Answer Sheet 2 with a single line through the centre.