Each medal has a jade inlay, a flat jade disk with a hole in the center.

每块奖牌都有碧玉镶嵌，其形状扁平，中间有孔。

youdao

Drilling on inclined surfaces has such problems as the decrease of hole accuracy and damage of tools compared with the drilling on flat surfaces.

斜面上钻孔与平面上钻孔相比，由于加工初期条件差，孔的相对位置精度低，刀具更容易折损。

youdao

Centipede seam drilling capacity is very strong, it tends to sensitive antennae and flat panels on the first hole to test the joints, rocks and through most of the land or habitat gaps.

蜈蚣钻缝能力极强，它往往以灵敏的触角和扁平的头板对缝穴进行试探，岩石和土地的缝隙大多能通过或栖息。

youdao

The only hole I couldn't knock out was the one around a flat, essentially 0% return.

FORBES: Break Their Crystal Balls

The sample comes from a hole about 2.5 inches deep drilled on Feb. 8 in a flat plate of sedimentary bedrock that the space agency managers have named "John Klein" in memory of a Mars Science Laboratory deputy project manager who died in 2011.

WSJ: Rover on Mars Extracts First Rock-Core Sample