You get sick and then you die, suggesting that sleeping is good to keep you healthy.

而是慢慢地生病死去，这表明睡眠对保持健康非常重要。

耶鲁公开课 - 心理学导论课程节选

Our immune system's function is to keep us healthy in the face of an environment where there are lots of things that could potentially harm us.

我们免疫系统的功能就是保持自身健康,在面对危机四伏的环境时,使我们免受伤害

耶鲁公开课 - 生物医学工程探索课程节选