C The idea of being able to walk on water has long interested humans greatly. Sadly, biologicalfacts prevent us ever accomplishing such a thing without artificial aid--we simply weigh too much,and all our mm pushes down through our relatively small feet, resulting in a lot zxxkof pressure thatmakes us sink. However, several types of animals can walk on water. One of the most interesting is thecommon basilisk Basilicusbasilicus, a lizard native to Central and South America. It canrun across water for a distance of several meters, avoiding getting wet by rapidly hitting the water'ssurface with its feet. The lizard will take as many as 20 steps per second to keep moving forward.For humans to do this, we'd need huge feet that we could bring up to our ears in order to create adequate "hitting. “ But fortunately there is an alternative: cornflour. By adding enough of this common thickeningagent to water (and it does take a lot), you can create a "non-Newtonian" liquid that doesn't behavelike normal water. Now, if the surface of the water is hit hard enough, particles in the watergroup together for a moment to make the surface hard. Move quickly enough and put enough force intoeach step, and you really can walk across the surface of an adequately thick liquid of cornflour. Fun though all this may sound, it's still rather messy md better mad about in theory than carriedout in practice, if you must do it, then keep the water wings handy in case you start to sink--and takea shower afterward! 44. Walking on water hasn't become a reality mainly because humans A. are not interested in it B. have biological limitations C. have not invented proper tools D. are afraid to make an attempt 45. What do we know about Basiiliusbasilicus from the passage? A. It is light enough to walk on water. B. Its huge feet enable it to stay above water. C. It can run across water at a certain speed. D. Its unique skin keeps it from getting wet in watch 46, What is the function of the cornflour according to the passage? A. To create a thick liquid. B. To turn the water into solid. C. To help the liquid behave normally. D. To enable the water to rove rapidly. 47. What is the author's attitude toward the idea of humans' walking on water? A, It is risky but beneficial. Il. It is interesting and worth trying. C. It is crazy md cannot become a reality. D. It is impractical thigh theoretically possible. 【查看更多】
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________there are a large number of chemical factories, the air is likely to be polluted
