Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the
correct answer to each of the questions from 33 to 40.
Early peoples had no need of engineering works to supply their water. Hunters and nomads camped near
natural sources of fresh water, and populations were so sparse that pollution of the water supply was not a serious
problem. After community life developed and agricultural villages became urban centers, the problem of
supplying water became important for inhabitants of a city, as well as for irrigation of the farms surrounding the
city. Irrigation works were known in prehistoric times, and before 2000 BC the rulers of Babylonia and Egypt
constructed systems of dams and canals to impound the flood waters of the Euphrates and Nile rivers, controlling
floods and providing irrigation water throughout the dry season. Such irrigation canals also supplied water for
domestic purposes. The first people to consider the sanitation of their water supply were the ancient Romans, who
constructed a vast system of aqueducts to bring the clean waters of the Apennine Mountains into the city and built
basins and filters along these mains to ensure the clarity of the water. The construction of such extensive watersupply systems declined when the Roman Empire disintegrated, and for several centuries local springs and wells
formed the main source of domestic and industrial water.
The invention of the force pump in England in the middle of the 16th century greatly extended the
possibilities of development of water-supply systems. In London, the first pumping waterworks was completed in
1562; it pumped river water to a reservoir about 37 m above the level of the River Thames and from the reservoir the
water was distributed by gravity, through lead pipes, to buildings in the vicinity. Increased per-capita demand has
coincided with water shortages in many countries. Southeast England, for example, receives only 14 per cent of
Britain's rainfall, has30 per cent of its population, and has experienced declining winter rainfall since the 1980s.
In recent years a great deal of interest has been shown in the conversion of seawater to fresh water to
provide drinking water for very dry areas, such as the Middle East. Several different processes, including
distillation, electrodialysis, reverse osmosis, and direct-freeze evaporation, have been developed for this purpose.
Some of these processes have been used in large facilities in the United States. Although these processes are
successful, the cost of treating seawater is much higher than that for treating fresh water.
From A. Briggs’ article on culture, Microsoft® Student 2008
Early peoples didn‟t need water supply engineering works because .
they had good ways to irrigate their farms
their community life had already developed
there was almost no dry season in prehistoric times
natural sources of fresh water nearby were always available
D. natural sources of fresh water nearby were always available
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