Learn Italian: Non mangio mai il cavolo.

In Italian, when a negative word like mai comes after the verb, you must put non before the verb. Unlike in English, this double negative doesn't cancel out; it just makes the sentence negative. Literally, it translates to "I do not eat never".

Why does the sentence use il cavolo instead of just cavolo? English doesn't use "the" here.

In Italian, when you talk about a general category of things, like a type of food you eat or avoid, you must use the definite article (like il, la, or i). Even though we just say "cabbage" in English, Italian requires il cavolo to mean cabbage in general.

Could I start this sentence with io (I)?

Yes, you could say Io non mangio mai il cavolo. However, because the -o ending on mangio already makes it clear that "I" am the one eating, the pronoun io is usually left out. You would only add it to emphasize that you never eat cabbage, perhaps in contrast to a friend who loves it.

I have heard Italians say cavolo when they are frustrated. Does it mean something else too?

Yes! While it literally means cabbage, cavolo is very commonly used as a mild exclamation similar to "heck" or "darn" in English. For example, che cavolo! means "what the heck!". In this sentence, however, it is just the literal vegetable.