In the following sentence:
Il est de formation classique.
The translation I found is He is classically trained., but I don't understand the grammatical structure of the sentence.
It is clear that il is a subject and est is a verb. And I think classique is an adjective that modifies formation (noun). But why is formation, which is a feminine noun, used in the form of de formation, not de la formation?
And also, why does the sentence mean trained in English? For me, It is the classical formation. sounds more natural...