They were twirling a brace drill.

他们当时正在转动曲柄钻。

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The cutting part of a drill usually pointed and threaded and is replaceable in a brace or bitstock or.

钻机的切割部分；通常是尖头的有螺旋状图案并且可以更换用在柱柄或上。

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Be careful not to brace with your palms at any point of this drill, but spear with the fingertips.

小心不要支撑与你的手掌在任意点的，但枪钻的指尖。

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But many here are beginning to brace for change as the Illinois Legislature considers regulations that could set off a rush among energy companies to drill deep in the southern Illinois bedrock for oil and natural gas.

NPR: Scenic, Struggling S. Illinois Braces For Oil Rush