It's been estimated that 31 percent of drivers will fall asleep at the wheel at least once in their life, and in the US, the statistics are pretty good: 100,000 accidents on the freeway have been associated with tiredness, loss of vigilance, and falling asleep -- a hundred thousand a year.
据估计，31%的司机 一生中至少有一次在开车时睡着了， 在美国，统计数字显示惊人： 在高速公路上发生的10万起交通事故 与疲倦，放松警惕， 和打瞌睡有关。