How to count the uncountable nouns
When we want to count the uncountable nouns, you have to put a phrase in front of the word.
Examples:
a bar of white chocolate, 3 bars of white chocolate
a bottle of milk / juice, four bottles of milk / juice
A jar of coffee / jam, three jars of coffee / jam
a carton of milk / juice, 4 cartons of milk / juice
a bowl of ice, a few bowls of rice
** HINT **
“Milk” and “jam” are uncountable, but “carton”, “bottle” and “jar” are countable.