钻头必须缓慢转动，以保证钻孔平整光滑。The drill should be slowly rotated to ensure a clean hole.打钻和提钻时要保持钻头平稳。Keep the drill steady while it ascends and descends.你得拆开这个钻头。You'll have to disassemble the drill....
He slipped and fell on an airplane gangway as the cameras rolled.在摄像时他不慎滑倒在飞机座位间的通道上。He slipped and fell on an airplane gangway as the cameras rolled...在摄像时他不慎滑倒在飞机座位间的通道上。Walking along the narrow gangway of the theater,...
本节只讨论其中的两类: 金属离子钝化剂和过氧化物分解剂.Only two types will be included in present discussion: metal - ion deactivators and peroxide decomposers.为方便起见,材料分为三大类: 金属, 塑料或聚合物和陶瓷.It is convenient to divide materials into three main types...