"She drinks coffee with milk."

Translation: Αυτή πίνει καφέ με γάλα.

[deactivated user]

Γιατί είναι "καφές" wrong?

[wyqtor]

Because it is accusative: πίνει τον καφέ.

[Grzegorz512]

Why "Αυτή πίνει τον καφέ με γάλα" is wrong?

[Hans339197]

I wrote: αυτή πίνει το καφέ με γάλα
and I got the above translation as correct solution.
Sometimes the correct solution is with article, sometimes correct is defined as without. I would like to know the exact rule for one or the other translation.

[D_..]

αυτή πίνει τον καφέ με γάλα = she always drinks (any) coffee with milk, that's how she drinks her coffee ('all/any coffee' is implied, that's why the definite article is there)
αυτή πίνει καφέ με γάλα = she's drinking coffee with milk right now, that's her drink right now

αυτή πίνει το καφέ με γάλα = she drinks the brown with milk (καφές is masculine and therefore needs to be preceded by τον, otherwise καφέ is neuter and means brown) :)