Normal people drink 2500-3500ml of water daily, but the amount of water needs to be adjusted and increased or decreased according to the age group and season. For example, children can drink less than 2,500ml, but it is better to drink more than 1,500ml a day, and elderly people can drink less than 3,500ml a day, but more than 2,500ml because drinking too much water will increase the cardiovascular burden and aggravate hypertension. 3000ml or so. But if it is summer, more sweating and very intense exercise, you can properly add 500ml to the amount of water you drink before you can ensure the amount of water a person needs for the day.