Use of definite article with 'italiano'

In lesson 1.2 Maria asks: Parli italiano?     - no article before 'italiano'  - but later in the dialogue she asks: Da quanto tempo studi l'italiano?     -  Now we have a definite article before 'italiano'. And a further example of this is when Alex says: Studio l'italiano da un mese.      - Again the definite article is used.
Is there a rule as to when one should use the definite article?
Grazie.
Valerie

Hi Valerie,

you may find this topic useful:
https://members.rocketlanguages.com/members/forum/italian-grammar/parli-italiano-vs-parla-linglese

If you have any other questions, don't hesitate to ask!

Lucia