And, they strike a thin foil of metal.

让它们去撞击金属箔。

youdao

The idiom "to strike while the iron is hot" comes from the black-smithing practice of heating up metal, then striking it when it is malleable to shape it.

“趁热打铁”这个习语来自铁匠打铁的做法，即一边将铁烧热，一边趁铁可塑成形时不停地锤打。

youdao

And, they strike a thin foil of metal.

让它们去撞击金属箔。

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