The instrument are designed with adjustable center holes at both ends that make its fitting and measuring rapidly and easy.

该仪器两端设计有可调心式中心孔，安装测量迅速方便。

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The machine drills the "center holes" for the hands as well as the "pilot holes" which will guarantee the positioning of the strip during blanking operations.

用机器钻出安装指针的中心孔及导向孔，以确保铜条在冲切工序固定位置。

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They stacked rocks with center holes (tube or doughnut shaped) from the surface to the deep stone layer as a guide for their drills (similar to today's guide tubes).

管状或中空管状的中心孔从地表到深石岩石层放满石头，以作为铁转的探头，作用类似今天的导管。

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This one, though, was shot through with bullet holes: three bullet holes to the center and another shot nicked off the top.

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As it happens, the coffee-like stains that he and his colleagues had been trying to remove with fast-drying solvents was actually the solution to his problem, since they remained in contact with each other as they dried and preserved conductivity, but left about 95 percent of the light through the holes in the center, thereby making the screen itself almost fully transparent.

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This finding is at odds with the current thinking about how supermassive black holes form at the center of new galaxies, which makes it of particular interest to astronomers.

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