Come mai?

A subscriber has asked about the common but difficult-to-translate expression come mai.

For starters, let’s take it apart.

Come (how) is easy enough and mai (never, ever) is as well. So we would be inclined to translate come mai as “ how ever.” With a bit of moving the words around, we could come up with:

Come riuscirai mai a farlo?
How are you ever going to be able to do that?

But what we're examining in this lesson is the idiomatic expression come mai as a unit, because, yes, it can stand on its own or be inserted as is, into a question or certain kinds of statements.

It’s most easily translated as “how come?” “How come” is another way to say “why.” “How come” is actually short for “how did it come about that” and dates from the mid-1800s. We can also translate it as “how is it that...” So we could say that come mai is another way of saying perché when perché means “why.” You may ask: When does perché not mean “why?” See this lesson to find out!

Come mai often expresses surprise at things being different from what one expects, so it’s an expressive way of saying “why.” In certain contexts where there is intense surprise at someone’s actions or decisions, it can even be translated as “why on earth?”

Come mai non hai tolto la pentola dal fuoco?
Why on earth didn’t you take the pot off the burner?

But come mai can also be a less aggressive way to say perché in certain situations. After all, with come mai, you are interested in knowing the other person’s reasons for doing something. So it’s not a cold, indifferent question. You may also be giving someone the benefit of the doubt. As an example, let’s say that the other person is usually reliable, but this time they messed up. Come mai? You’re wondering about it.

The question, perché non mi hai chiamato? asked with a certain tone, can be almost accusatory or dry, but come mai non mi hai chiamato implies that I was really expecting you to have called me, and so you must have a good reason for not calling me.

Let’s look at some examples from Yabla videos.

Ma sai che anche io mi sento un po' stanca, chissà come mai.

But you know that I feel a little tired, too, who knows why?

Caption 27, Anna e Marika - Il verbo avere
Play Caption

The speaker could easily have said the following, and meant pretty much the same thing:

Ma sai che anche io mi sento un po' stanca, chissà perché.

But come mai gives us the idea that she is truly wondering why she is tired. She shouldn’t be. She slept fine.

Io so perché si chiama arena.

I know why it's called an arena.

-Ah, è vero!

-Oh, that's right!

Come mai si chiama arena?

How come it's called an arena?

Captions 22-24, Marika e Daniela - Colosseo, interno
Play Caption

In the above example, the speaker could easily have used perché. But come mai implies some real curiosity. It might indicate the wish to hear the long answer rather than the short one.

Let’s remember that perché can mean both “why” and “because.” Come mai, on the other hand, is mostly used in questions but also in some negative or questioning statements, such as:

Non so come mai arrivo sempre in ritardo.
I don’t know why I always come late.

Come mai never means “because.”

In the following example, Mimì of "La Bohème" is talking about a change in Alfredo’s behavior. Since she was jolted by this change, she uses come mai.

Era diventato geloso.

He had become jealous.

Non capivo come mai.

I couldn't understand why.

Captions 27-28, Anna presenta - La Bohème di Puccini
Play Caption