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Passage 1 The changing profile of a city in the United States is apparent in the shifting definitions used by the United States Bureau of the Census. In 1870 the census officially distinguished the nation’s "urban" from its "rural" population for the first time. "Urban population" was defined as persons living in towns of 8,000 inhabitants or more. But after 1900 it meant persons living in incorporated places having 2,500 or more inhabitants. Then, in 1950 the Census Bureau radically changed its definition of "urban" to take account of the new vagueness of city boundaries. In addition to persons living in incorporated units of 2,500 or more, the census now included those who lived in unincorporated units of that size, and also all persons living in the densely settled urban fringe, including both incorporated and unincorporated areas located around cities of 50,000 inhabitants or more. Each such unit, conceived as an integrated economic and social unit with a large population nucleus, was named a Standard Metropolitan Statistical Area (SMSA). Each SMSA would contain at least (a) one central city with 50,000 inhabitants or more or (b) two cities having shared boundaries and constituting, for general economic and social purposes, a single community with a combined population of at least 50,000, the smaller of which must have a population of at least 15,000. Such an area included the county in which the central city is located, and adjacent counties that are found to be metropolitan in character and economically and socially integrated with the county of the central city. By 1970, about two-third of the population of the United States was living in these urbanized areas, and of that figure more than half were living outside the central cities. With the Census Bureau and the United States government used the term SMSA (by 1969 there were 233 of them), social scientists were also using new terms to describe the elusive, vaguely defined areas reaching out from what used to be simple "towns" and "cities". A host of terms came into use: "metropolitan regions", "polynucleared population groups", "metropolitan clusters", and so on. Prior to 1900, how many inhabitants would a town have to have before being defined as urban
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61. Sweden has got a population of only 8 million, but it is a large country with an area of 450,000 square kilometers. 62. There are frontiers with Norway to the west and Finland to the east and the distance from the southern to northern coasts is very long. In 1977, the Swedish king was Charles XVI and the Prime Minister was Mr. Fielding. 63. Sweden is neutral and is not a member of the European Economic Community (EEC). Its last war was from 1813 to 1814 when its army under the first Bemadotte king of Sweden was at the battle of Leipzig against Napoleon. 64. Sweden’s principal trading partners are Germany and Great Britain. Her main exports are machinery, paper, cars and iron and steel. In 1971, machinery was 26% and cars 10% of her exports, and exports were greater than imports by 2,000 million crowns. Between 1963 and 1971 there was an increase of 61% in industrial production. Sweden is a wealthy country. Taxes are high but her people are very well-off. With Denmark and Norway, Sweden has got her own airline, SAS. Her air force is very strong and she has got her own SAAB fighters. 65. Sweden is famous for the Nobel Prize, for the films of Ingmar Bergman, for the plays of Strindberg, and for Volvo cars. Stockholm is one of the loveliest cities in the world.
Hawaii, the newest state in the United States, is a (21) of eight large islands and many small (22) in the Central Pacific Ocean, about 2,200 miles west of San Francisco. Hawaii was probably (23) about 750 A. D. , by (24) from the other Pacific islands. The first Europeans (25) Americans to visit it were the British Captain James Cook and his (26) in 1778. James named his discovery the Sandwich Islands (27) the sponsor of his expedition, the Earl of Sandwich. Twelve years later, the others from Europe and the new United States began to settle in the islands. These "westerners" brought (28) to Hawaii. They brought new diseases, which the Hawaiians had no (29) to; they brought alcohol, which many Hawaiians became (30) to; they brought a new religion which (31) the old values and forced the islanders to (32) their old culture and (33) to a new one. Many Americans settled in Hawaii, and in 1893, they (34) the queen and (35) Hawaii a republic. Sandford Dole, a missionary’s son, was made president. In 1898, the United States (36) the islands, and it became a (37) of the United States in 1900. On December 7th, 1941, the Japanese (38) Pearl Harbor, Hawaii. This attack (39) the entrance of the United States to the Second World War. In 1959, the United States Congress (40) Hawaii to statehood, making it the fiftieth state in the United States. For the first time in about 200 years, Hawaiians were able to participate in the electoral process.
In recent years a new farming revolution has begun, one that involves the manipulation of life at a fundamental level—the gene. The study of genetics has (51) a new industry called biotcehnology. As the name suggests, it (52) biology and modern technology through such techniques as genetic engineering. Some of the new biotech companies specialize in agriculture and are working feverishly to (53) seeds that give a high yield, that (54) diseases, drought and frost, and that reduce the need for hazardous chemicals, If such goals could be achieved, it would be most (55) . But some have raised concerns about genetically engineered crops. In nature, genetic diversity is created within certain (56) . A rose can be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering, (57) usually involves taking genes from one species and inserting them into another in an attempt to transfer a desired characteristic. This could mean, for example, selecting a gene which leads to the production of a chemical with anti-freeze (58) from an artic fish, and inserting it into a potato or strawberry to make it frost, resistant, in essence, then, biotechnology allows humans to (59) the genetic walls that separate species. Just like the green revolution, (60) some call the gene revolution contributes to the problem of genetic uniformity-some say even more so (61) geneticists can employ techniques such as cloning and (62) culture (培养) and processes that produce perfectly (63) copies. Concerns about the erosion of biodiversity, therefore, remain. Genetically altered plants, however, raise new (64) ,such as the effects that they may have on us and the environment. "We are tlying blindly into a new era of agricultural biotechnology with high hopes, few constraints, and little idea of the potential (65) ," said science writer Jeremy Rifkin.
The housewives learnt about the information of free goods ()
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