1. 3 * 300ml = 3 * .3 liters = .9 liters
2 and 3 are even less, but 2 = .005 liters, 3 = .015 liters
4. is a possibility, but that is too much water.
It would be better to express all in liters, but you would want them to drink more than .0015 liters a day.
1. Drink more than three 300-milliliter bottles of water every day.
2. Drink over 0.5-milliliter of bottles of water a day.
3. Drink three 0.5-ml of bottles of water every day.
4. Drink three one-liter bottles of water a day.
(Can we use all the expressions?)
2 answers
PsyDAG is right about the amounts of water. Try these:
Drink more than three half-liter bottles of water a day.
Drink more than two liters of water a day.
The simpler you can make the phrasing, the easier it will be for others to understand.
Drink more than three half-liter bottles of water a day.
Drink more than two liters of water a day.
The simpler you can make the phrasing, the easier it will be for others to understand.