Learn Swedish: Vore det okej att låna bastun? - Would it be okay to borrow the sauna?

Vore is a special, one-word way to say 'would be'. While you could absolutely say Skulle det vara okej, using vore makes the sentence shorter and often sounds a bit more polite or natural in hypothetical questions. Since this is a yes/no question, the verb vore is placed at the very beginning of the sentence.

The translation says 'borrow the sauna', but in English we usually say 'use the sauna'. Why use låna here?

In Swedish, it is extremely common to use låna (to borrow) for things you want to use temporarily, even if you cannot literally pick them up and take them with you. You will frequently hear Swedes ask to 'borrow' a restroom (låna toaletten), a phone, or in this case, a sauna (bastun).

What is the base form of bastun and how does its definite form work?

The base word is en bastu (a sauna). Because it is an en-word that already ends in a vowel, you only need to add an -n to make it definite: bastun (the sauna). It is in the definite form here because the speaker is asking about a specific sauna, likely the one in the host's house or apartment building.

Why do we need the word att before låna?