本文通过对中国古代金属制品的研究后发现，中国在战国时期的一些青铜兵器上，留下了大量的机械加工的痕迹。
By studying Chinese ancient metal products, we find, there were a lot of machining tracks in some bronze weapons of Warring States.
本文通过对中国古代金属制品的研究后发现，中国在战国时期的一些青铜兵器上，留下了大量的机械加工的痕迹。
By studying Chinese ancient metal products, we find, there were a lot of machining tracks in some bronze weapons of Warring States.
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