题目内容
By the end of this century this may not be mere speculation. Scientists are already looking into the possibility of using some of the available ice in the Arctic and Antarctic. In these regions there are vast ice-caps formed by snow that has fallen over the past 50,000 years. Layer upon layer of deep snow means that, when melted, the snow water would be pure, not salty as sea-ice would be. There is so much potential pure water here that it would need only a fraction to turn much of the desert or poorly irrigated parts of the world into rich farmland. And what useful packages would come in! It should be possible to hack off a bit of ice and transport it! Alternatively perhaps a passing iceberg could be captured. They are always breaking away from the main caps and floating around, pushed by currents, until they eventually melt and are wasted.
Many icebergs are, of course, much too small to be towed any distance, and would melt before they reached a country that needed them anywhere. It would be necessary to harness one that was manageable and that was big enough to provide a good supply when it reached us. Engineers think that an iceberg up to 11 kilometres long and 2 kilometres wide could be transported if the tug pulling it was as big as a supertanker! Even then they would cover only 32 kilometres every day. However, once the iceberg was at its destination, say at one end of Hong Kong harbour, more than 7,000 million cubic metres of water could be taken from it! That would probably be more than enough for Hong Kong even in the hottest summer! But no doubt a use could be found for it.
Apparently, scientists say, there would not be too much wastage in such a journey. The larger the iceberg, the slower it melts, even if it is towed through the tropics. This is because when the sun has a bigger area to warm up, less heat actually gets into the iceberg. The vast frozen center would be unaffected.
Even with the giant tug that would have to be available to tow an iceberg seven miles long, the voyage would take many months from the Antarctic to Hong Kong, for example, but as stronger engines are built and more is known about sea currents, the journey could get shorter and shorter and thus the wastage less and less. Airline pilots have learnt to use jet streams ten miles above the earth to increase speed and save fuel so, surely, a boat towing an iceberg could make use of fast-flowing currents and avoid warmer water.
The main idea of the first paragraph is that______.
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It was the forearm they uncovered which______.
A．Pollution and population explosion.B．Universal love and understanding between people
听力原文： In some ways, children should be treated as mature people. For one thing, adults should not use baby talk with children, using real words with children helps them develop their language skills more quickly. In most cases, children admire their parents or their elders, and they want to understand and communicate with adults in the way adults do among themselves. Baby talk with children often makes them feel patronized, frustrated, and confused. So, animals should be called "cows" or "dogs", not "mu-mews" and "bow-ows". Second, parents should be consistent when disciplining their children. For example, If a parent tells a child "You cannot have desert unless you put away your toys", it is important that the parent follow through on the warning. By being consistent, parents will teach children responsibility and give them a stable center around which to grow. Finally and most important, children should be encouraged to join in such off-class activities as the boy scouts, the children's band and the teen-court. In doing so, parents will thus be helping their children prepare for the complex decisions that they will have to deal with in later life.
(35)
A．Eating more food.B．Getting some exercise.C．Taking some medicine.D．Quitting his job.
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