1. This usually causes only minor discomfort, such as a skin rash, headache or sleepiness. 这通常只会引起轻微的不适，如皮疹、头痛或嗜睡。
2. Most experts in sleep behavior agree that there is virtually an epidemic of sleepiness in the nation. 大多数研究睡眠行为的专家都认为，在这个国家，嗜睡实际上是一种流行病。
3. Although the pressure of the cabin is adjusted to prevent altitude sickness, you could still experience sleepiness or a headache. 虽然机舱压力可以被调节，以避免人体发生高空反应，但你仍会感到困倦或头痛。
4. Their yawning seems to have nothing to do with sleepiness or boredom—quite the reverse—but it does precede a change in activity level. 他们打哈欠似乎与困倦或者无聊没有任何关系，但恰恰相反，打哈欠这一行为的确出现在了活动水平的变化之前。
5. A 2008 British study found that compared to getting more nighttime sleep, a mid-day nap was the best way to cope with mid-afternoon sleepiness. 2008年英国的一项研究发现，与获得更多的夜间睡眠相比，午间小睡是应对午后困倦的最佳方式。
