题目

Water shortage is one of the world's biggest challenges. The World Health Organization (WHO) thinks one in three people globally do not have easy access to clean water. Desalinating (给……脱盐) ocean water could help. But currently-available desalination units typically require high-pressure pumps to push water through filters (过滤器), which makes it difficult to reduce their size without influencing the energy-efficiency of the device. Meanwhile, they are too expensive to set up widely.Now, Massachusetts Institute of Technology (MIT) researchers have developed a convenient desalination machine. Unlike traditional desalination units, the MIT machine uses electricity to remove the salt and other small things from the ocean water. More importantly, the suitcase-sized device needs less power to run. It can also be powered by a small solar panel that costs less than $50. The lack of filters and the low electricity requirements make the machine extremely cheap to set up. "Ease of use was one of the main motivations for creating the device." said one researcher.After running lab experiments using water with different salinity (盐度) levels, they field-tested the device at Boston's Carson Beach. The researchers set the box near the shore and put the tube into the water. In about half an hour, the device had filled a plastic cup with clear, drinkable water.The researchers believe their invention can deliver drinking water meeting WHO quality standards with a push of a button. Meanwhile, a smartphone app allows the user to control the unit wirelessly and receive real-time data on power consumption and water salinity. It also sends out information when the water is drinkable.The MIT team is now exploring ways to bring their machine to market. They believe it will benefit residents of small islands or those running away from natural disasters in the future. （1） What do we know about the current desalination units? A . They cannot work efficiently. B . They are usually large in size. C . They were developed by MIT. D . They cannot stand high pressure. （2） Which aspect of the new desalination device is Paragraph 2 mainly about? A . The original purpose. B . The working process. C . The practical advantages. D . The major components. （3） What makes the researchers confident in their invention? A . That it is user-friendly and effective. B . That it can provide lots of real-time data. C . That it can be supported by several smartphone apps. D . That it has successfully passed many lab experiments. 答案： B C A

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