文勇的新托福黄金&ccedil

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Unformatted text preview: Ataturk and other dams in Turkey? ○To contrast the Euphrates River with other exogenous rivers ○To illustrate the technological advances in dam building ○To argue that dams should not be built on the Euphrates River ○To support the idea that international river­basin agreements are needed 4. According to paragraph 2. Which of the following is true of the Nile River? ○The Nile's flow in its desert sections is at its lowest during the dry season ○The Nile's sources are located in one of the most arid zones of the world ○The Nile's annual floods bring fertile silts and water to its lower valley ○The Nile's periodic flooding hinders the growth of some crops 362 Mail@liuwenyong.com 在在在在在在 www.liuwenyong.com 在在在在在在在在在在在在在在在,在在在在在在在在在在 Paragraph 5 在 Deserts contain large amounts of groundwater when compared to the amounts they hold in surface stores such as lakes and rivers. But only a small fraction of groundwater enters the hydrological cycle­feeding the flows of streams, maintaining lake levels, and being recharged (or refilled) through surface flows and rainwater. In recent years, groundwater has become an increasingly important source of freshwater for desert dwellers The . United Nations Environment Program me and the World Bank have funded attempts to survey the groundwater resources of arid lands and to develop appropriate extraction techniques. Such programs are much needed because in many arid lands there is only a vague idea of the extent of groundwater resources. It is known, however, that the distribution of groundwater is uneven, and that much of it lies at great depths. 5. The word dwellers in the passage is closest in meaning to ○settlements ○farmers ○tribes ○inhabitants 6. Paragraph 5 supports all of the following statements about the groundwater In deserts EXCEPT: ○The groundwater is consistently found just below the surface ○A small part of the groundwater helps maintain lake levels ○Most of the groundwater is not recharged through surface water ○The groundwater is increasingly used as a source of freshwater Paragraph 6 在 Groundwater is stored in the pore spaces and joints of rocks and unconsolidated (unsolidified) sediments or in the openings widened through fractures and weathering. The water­saturated rock or sediment is known as an "aquifer". Because they are porous, sedimentary rocks, such as sandstones and conglomerates, are important potential sources of groundwater. Large quantities of water may also be stored in lime stones when joints and cracks have been enlarged to form cavities. Most limestone and sandstone aquifers are deep and extensive but may contain ground waters that are not being recharged. Most shallow aquifers in sand and gravel deposits produce lower yields, but they can be rapidly recharged. Some deep aquifers are known as "fossil waters. The term "fossil" describes water that has been present for several thousand years. These aquifers became saturated m...
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