Английский язык. How much water do we need a day? Why do we need to drink water? When do we drink water?

How much water do we need a day? - We need to drink about 2,5 litres of water every day, but it depends on your body.Why do we need to drink water? - We need to drink water to be healthy and keep ourself alive.When do we drink water? - We always drink water during the whole day, especially when it\'s hot.