Most people who travel long distances complain of jetlag(喷气飞行时差反应). Jetlag makes business travelers less productive and more prone 61to making mistakes. It is actually cause by 62disruption of your body clock-a small cluster of brain cells that controls the timing of biological 63functionss . The body clock is designed for a 64regular rhythm of daylight and darkness, so that it is thrown out of balance when it 65experiences day light and darkness at the wrong times in a new time zone. The 6
