根据短文内容填空，每空限填一词。
Of all the things we eat and drink, water is the most important. Not many people understand this, but it
is quite true. The human body (人体) can go without food for a long time, but two or three days without
water usually make people dead.
Many people don't understand how much water the human body needs to work well and many people
do not drink enough, especially (尤其) in hot weather. Most people drink when they are thirsty, but they
often need more water especially when they take exercises.
A man's body is 65 to 75 percent (百分之…) water. If we do not have enough water, we feel tired
and may become ill.
The most important drink is 1_______, People can 2_______ for a long time without food, but they will
3_______ if two or three days 4_______ water. In 5_______ weather, many people do not drink 6_______
water, because they don't know how much water they 7_______. People should know when they take
exercises, they need 8_______ water. The water in the man's body is 9_______ more than other matters
(物质) We'd better have enough water, 10_______ we may get ill.