The final step came when steam was introduced into the cylinder to drive the piston backward as well as forward, thereby increasing the speed of the engine and cutting its fuel consumption.
最后一步是将蒸汽引入气缸，使得活塞前后推动，从而提高了发动机的速度，降低了燃料消耗。
2
Now all of the BIOS will allow detection of the floppy disk drive in the list of backward-shift, which can reduce the normal start-up time a few seconds.
现在所有的BIOS都允许将软盘驱动器在检测列表中向后移，从而可以将正常的启动时间减少几秒钟。
3
This paper has set up a computer aided diagnostic expert system for automotive drive line by way of forward and backward combined reasoning and depth optimal theory.