in Swedish professor an academic university title and the name for the highest educated teachers at a university. Lärare (teacher) is just any person who teaches.
In academia, we usually call the person who teaches at a university or a college AND with a PhD or a licentiate degree as "a lecturer", en lektor på Svenska.
I agree with eal_duo as for the model utterance; having the definite species "professorn" indicates the need of translating it "the professor". - So, there is some discrepancy between exercise stuff and the solution!
Is "Professor" used in the British style, where it's a prestigious title that only some university faculty have, or like the American style where it's anyone who teaches at a university?