back_and_forth_vibration_有道手机词典

1.A vibration, by its nature, is back and forth, a pull and release with bounce back and a return to a pull.
振动的本质就是来来回回，牵拉再释放使其反弹再牵拉的过程。
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2.Sound is caused by vibrations. A vibration is a back and forth movement.
声音是由振动引起的。振动就是往复运动。
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