primary drive

The primary drive gear ( crankshaft gear) and the primary driven gear are the source of noise due to their high speed and bigger reduction ratio.

作为摩托车初级传动的曲轴齿轮及初级从动齿轮，由于转速高及降速比大，是产生噪声的主要因素。

Then reformat ( wipe ) your primary hard drive and reinstall your operating system of choice.

然后格式化你主要的硬盘并重新安装你的操作系统.

Mechanical disk drive technology has served as the primary storage medium for decades.

机械磁盘驱动器技术已经作为主要存储体数十年.

The sleep insufficiency is primary factor that causes weary drive.

睡眠不足是造成疲劳驾驶的主要因素.

The hydrocarbon expulsion efficiency of source rock primary migration is usually high because ofof natural drive.

因油气初次运移为自然驱替,因此源岩的排烃效率较高.