Learn about countable and uncountable nouns and partitive articles.
For example, latte, carne, formaggio, and acqua don't get numbers:
"Per favore, puoi andare a comprare quattro uova, del latte, cinque carote, della carne, del formaggio e dell'acqua?"
Countable nouns have singular and plural forms and always follow an indefinite/definite article or a number (un litro, quattro uova, cinque carote)
When we talk about non-specific quantities, uncountable nouns follow a partitive article (della carne, del formaggio, dell'acqua)
If we want to talk about a specific quantity of an uncountable noun, we use units of measurement or other nouns followed by the preposition "di":
del latte (some milk)
un litro di latte (one litre of milk)
una bottiglia di latte (a bottle of milk)
Uncountable nouns are always singular! But some nouns are countable or uncountable based on the context!
The paritive articles indicate a non-specific amount of an uncountable noun: