What I found is that written evidence for knocking on wood (and for the history of gesture as a whole) is remarkably sparse. In the Penguin Guide to Superstitions, folklorist Steve Roud offers a skeptical take on the provenance of knocking on wood due to the near total absence of written records about it:
Что думаешь? Оцени!
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This is one of five facilities on the icy continent run by the British Antarctic Survey (BAS), the UK's polar research institute.，推荐阅读雷电模拟器官方版本下载获取更多信息
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