In English you can't use a singural noun as subject of a sentence if it is without an article, can you? You either say ”A girl eats.” or ”The girl eats.”, but not ”Girl eats.”
This is true in Romanian both for the singular and for the plural: the noun that is subject of the sentence must have either a definite or an indefinite article.
So ”fată” (= ”girl”) or ”fete” (= ”girls”) can't be used as a subject because they do not have any kind of article.
No, actually for all the sentences in English where the subject is a plural without article we translated them in Romanian only with the plural with definite article (in this case ”fetele”).
We explained the difference like this: when you don't use ”the” you make general statements (”Cats are animals.”) and you refer to all the cats in the world; but when you use ”the” (”The cats drink milk.”) you refer to some cats in particular. Both are translated as ”pisicile” (=”the cats”), but for the reverse sentence we accept both English versions, with and without ”the”.