Most Windows PCs will exhibit a certain degree of slowness after some periodofusage (about 2 years or so).
大多数Windows电脑将展出经过一段时期的使用(约2年左右)一定程度的缓慢。
2
The volume table for oil storage tank will lose efficacy after a periodofusage due to factors like foundation deformation.
由于地基变形等原因，地下储油罐使用一段时间后罐体的变位会导致原标定的罐容表失效。
3
In early period, there were no half-measures: usage was either right or wrong, and it was the task of the grammarian not simply to record alternatives, but to pronounce judgement upon them.