【Sentences】
1.Drink water to stay hydrated.
喝水，让自己身体处于不缺水的状态。
stay+adj表示处于某种状态的意思，例如stay awake保持清醒，stay asleep一直睡着等等。
hydrated 有充足水分的
如：It's important for girls to keep their skin hydrated in winter.
女孩子一定要注意皮肤的冬天保湿工作。
2.Massage your neck and the backs of your hands to improve circulation.
按摩自己的颈部和手背，促进血液循环。
Massage vt. 按摩，揉
如：I want somebody to massage my shoulders.
我想要有人给我按摩肩膀。
Medical treatment by mechanical methods, such as massage.
机械疗法用机械方法(如按摩)对疾病进行治疗的方法
circulation在这里指的是“血液循环”。
3.Expose yourself to bright light, preferably natural daylight, to remind your mind and body that you should be awake.
把自己暴露在强光下，最好是自然光，给自己提神，让自己保持清醒。
Expose sb. to vt. 揭露，使暴露，使曝光，使面临
如：It's very foolish of the commander to expose his men to unnecessary risks.
这个指挥官让士兵们冒不必要的危险真是太愚蠢了。
You shouldn't expose the soldiers to unnecessary risks.
你不应该让士兵们冒不必要的危险。