Q. How much water one should drink everyday?

A . How much water one should drink is actually decided by urine output.
Adult person should pass 1.25 to 1.5 litrs of urine everyday. Naturally one should drink that much water which will cause this urine output .In sumer it will be more as you sweat a lot and in winter water requirement will be less .
In general drinking 2 to 4 litres of water is safe.