大部分人用单摆做，它们会碰撞，相互碰撞。
Most people do this with pendulums where they bounce these balls against each other.
大部分人用右手写字、工作。
今天大部分人锻炼用的哑铃更像是重量级的手摇铃，只不过没有铃锤。
The dumbbells most people exercise with today more closely resemble heavy hand-bells with their clappers taken out.
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