Russians first discovered these cast iron balls with single looped handles.

俄罗斯第一次发现这些单环把手铸铁球。

youdao

If you control normal spirals very good, then this maneuver isn't really difficult. You just need iron balls, and you can NOT make a single mistake.

如果你的螺旋做得非常好，这个动作不是很难，你只是需要胆大心细，不犯错误。

youdao

Waves of deafening sound come from a steel pipe spiraling over the scaffolding, within which a set of invisible iron balls circulate endlessly around the exhibition space.

一阵阵震耳欲聋的声响冲击着观众的耳膜，声音来源于脚手架支撑的钢管，其中的封闭铁球不停地沿着展厅四周盘旋滚动。

youdao

Which makes no sense at all as a monkey is, in archaic naval parlance, a brass triangle which iron cannon balls are piled up inside of.

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The teacher took us to the practice range, put the balls on the tees, and gave 6 or 7 iron clubs, saying that anyone who can hit over the net, I think it was about 70 yards away, did not have to pick up the balls that day.

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Iron clubs from the 17th to the early 19th century are rare because feather-filled balls could explode if hit inexpertly.

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