Translation:The wizard only uses magic when it is necessary.
About word order...
Could you say: "Troldmanden bruger magi kun når det er nødvendigt"?
No. In declarative main clauses, the clause adverbial comes after the subject + verb.
Perhaps "... bruger bar magi..." ? I'm not sure. There's a similar discussion in the English-to-Danish thread for the same sentence.
Thanks, Victor. Do you mean that the adverb "kun" has to follow the verb "bruger" rather than the object "magi"?
But just to confuse you a bit further: If we replace the word "magi" with a pronoun, the adverb will have to come after.
"Troldmanden bruger kun magi når det er nødvendigt."
"Troldmanden bruger det kun når det er nødvendigt."
Hah! Well, okay, I'm going to think of it as a descending scale of attraction/stickiness to the verb:
object pronoun (stickiest) -->adverb (less sticky) --> object noun (least sticky).
Thanks so much!