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(单词翻译:双击或拖选)
On our last program, we learned how water bugs2 manage to stand on the surface of a pond: The pads of their feet resist contact with the water just like wax paper does. This allows the bug1 to rest on the thin film of surface tension that naturally covers the pond. This surface tension film is caused by the strong attraction the surface water molecules3 have toward each other, as well as toward the water beneath them. While this is fine for standing4 on water, you might wonder how a water bug actually starts moving. After all, there’s virtually no contact between the bug’s feet and the water, so there’s no friction5 for the bug to push against. It would be like wearing slippery shoes on flat, wet ice-you might slide your feet around, but you couldn’t get anywhere.
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1 bug | |
n.虫子;故障;窃听器;vt.纠缠;装窃听器 | |
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2 bugs | |
adj.疯狂的,发疯的n.窃听器( bug的名词复数 );病菌;虫子;[计算机](制作软件程序所产生的意料不到的)错误 | |
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3 molecules | |
分子( molecule的名词复数 ) | |
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4 standing | |
n.持续,地位;adj.永久的,不动的,直立的,不流动的 | |
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5 friction | |
n.摩擦,摩擦力 | |
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