I would like to take this example as one of many which occur across DL Italian. If I take a closely related language, French, which I know and speak well, you would never say "Les éléphants mangent pain". That would sound like a strained anglicism. You would say "Les éléphants mangent le pain", or at least "Les éléphants mangent du pain". A noun in this context is always preceded by an article.
Is this not so in Italian? Or is this "bevono acqua" not "bevono l'acqua" construction really proper Italian?
Can an Italian native speaker advise?
My native language is English, but I was told that the use of definite articles in statements such as this are similar to how it is in English, except opposite.
In English, a general statement of habit omits the definite article: I eat bread. I drink water. In Italian, a general statement of habit uses the definite article: Mangio il pane. Bevo l'acqua.
In English, a statement referring to a specific instance uses the definite article: I eat the bread. I drink the water. In Italian, a statement referring to a specific instance omits the definite article: Mangio pane. Bevo acqua.
Most -- not all, but most -- verbs in Italian are regular, which means if you know what suffix the infinitive ends with, you can apply a simple template and know how to conjugate it.
Mangiare is a regular -are verb, which means you can apply the first template:
The stem already has an i at the end, so it gets absorbed into the "tu" suffix. There is no double-i verb ending.