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Of all the things we eat and drink, water is the most important. Many people don't understand this, but it is true.

People can livewithoutfood for a long time, but they may be ill or dead if they don't have water for two or three days.

Many people drink water when feel thirsty. They don't understand how much water adman's body needs. And they don't drink a lot, especially in hot weather. A man's body contains 65% to 70% water. If we don't have a lot of water, we may feel tired and become ill.

To keep healthy, we need to drink about eight glasses of water a day. So let's drink more water during the day and stay healthy.