听课
课程多端同步更新,充分利用零碎时间。做题
海量精选试题,想练就练,瞬间提分。答疑
网校名师24小时在线答疑解惑。直播
名师大咖面对面,有问有大收获多。Some of us feel well-rested after a solid eight hours of sleep. For others, closer to nine feels best. For others still, a little less will do. How much sleep we prefer to get is highly subjective -- but how much sleep we need is a bit more concrete.
我们中的一些人,睡足了8个小时后觉得无比神清气爽。对于另一些人来说,睡差不多9个小时为最佳。还有一些人,稍微不足这点时间刚刚好。我们更愿意睡多久是非常主观的——但是我们需要多少睡眠就是有那么一点具体有形的了。
After web analytics showed the vast popularity of the How Much Sleep Do We Really Need? feature of the National Sleep Foundation's (NSF) website, a panel of experts set about to reassure that the information provided there was the most accurate and up to date.