【正文】
analysis: ? 3. Tolerances on finish and dimensions play an important role in the final achievement or absence of practical production design. ?光潔度和尺寸公差在最終效果(成品)或者沒(méi)有實(shí)際加工的設(shè)計(jì)中起重要作用。 Sentenceanalysis: ? 5. Without needing to know how to operate a particular machine to attain the desired degree of surface roughness, there are certain aspects of all machining methods which should be understood by the design engineer. ? 設(shè)計(jì)工程師無(wú)需知道怎樣操作具體的機(jī)器來(lái)獲得