If you only got six hours' shut eye last night, there is no need to lose sleep over it.
如果昨天晚上你睡够了六个小时，那么你真的没有必要再继续睡下去了。
Scientists say that despite the widely held belief we need eight hours of sleep a night, six to seven hours is the natural amount.
尽管大多科学家都坚信一天需要睡八个小时，但是六个小时就已经是自然睡眠的足够时间了。