The slightest motion of a patient in bed creates friction between skin and sheets and results in loss of cells from the skin's outermost layer.
卧床病人最轻微的活动就会在皮肤和床单之间产生摩擦力，结果就会引起皮肤最外层脱落。
2
The general low level of friction on ice allows a skater to glide along the surface smoothly without friction stopping the motion as soon as it's begun.
冰面上摩擦力通常较低，这使得滑冰选手一俟启动，就能不受摩擦力牵绊，顺畅滑翔冰面。
3
If there were no friction, an object in (motion) would never come to a rest.