What we see is that there are in fact two entangled traditions of “knocking on things for good luck”: touching iron, and touching wood. We also find that they are widely distributed, but also have a pretty clear cluster around the Mediterranean and Europe.
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Цены на нефть взлетели до максимума за полгода17:55。一键获取谷歌浏览器下载对此有专业解读
* 1. 转换视角：将"追车"问题转为"到达时间"比较（后车时间≤前车 → 合并）；