Piot
abbr. 物质投入产出表（physical input-output table）
🗣️ 情景例句
I'd like to help you, but...
我很想帮助你，但是…
Custom is a second nature.
习惯是第二天性。
and so the tools of long ago have remained when even the bones of the men who made them have disappeared without trace.
因此，尽管制造这些工具的人的骨头早已荡然无存，但远古时代的石头工具却保存了下来。