112-學測-英文-文意選填-21-30

$~~~~$Water makes up more than half of our body weight. To sustain this amount of fluid in our bodies, plain water is considered our best choice, for it contains no sugar and no calories. Yet, is water always the healthiest drink we can ? Well, it depends on who and where we are, and what we’re doing.
$~~~~$Obviously, a physically person with an outdoor job under the sun will need to drink more fluid than a desk-bound person who lives and works in an air-conditioned place. But there’s more to it than that. When a person sweats, he loses water and salt, so he needs to replace both. Replacing lost fluid with just plain water means the body has too much water and not enough salt. To things out, the body will get rid of water by producing urine. For this reason, milk can actually be more than drinking water. Milk naturally contains salt and lactose, a sugar which the human body needs in small amounts to help stimulate water . Coconut water, which contains salt and carbohydrates, is also more functional than water at restoring and maintaining a normal fluid after exercise.
$~~~~$For the average person, however, water remains a very good for keeping hydrated—if you know how to drink it. The secret is: Never wait until the body is telling you you’re thirsty, since there must already have been significant changes in your body for it to eventually your consciousness. At that point, it might be well past the best moment to take in fluid. Also, drinking a lot of liquid in one go can cause more water to the body quickly and come out as urine. To this, you need to drink water throughout the day to maintain your hydration levels.