锋利的手动工具在两百万年前已经随处可见，人类挖掘出的最古老的长矛距今有40万年，而第一件有效武器出现在17000年前。

Sharpened hand tools have been around for twomillion years, yet the earliest spears to be dug up are a mere 400, 000years old and the first effective weapon a mere child at 17, 000 yearsold.

youdao

所以我不得不从速射武器的技术开始学习，第一件就是我的闹钟。

So I had to go back to the beginnings of rapid-fire technology and start my clock from there.

youdao