"He needs to rent a car."
Translation:Han behöver hyra en bil.
Well, modal verbs don't need it. But for a handful of common ones, it's irregular.
Do we say "He needs to that hire a car" in English? Cause that's sort of what att does, as far as I know.
Would "han behöver hyra bil" be wrong? Since I would think that, because you're just talking about a car in general, not a specific car, that you can just say "bil" and not "en bil"
Yes, that works too. There's a difference in meaning between måste and behöver in Swedish that you don't really seem to have in English, where native speakers tell me they use verbs like 'must', 'have to', and 'need to' interchangeably.