Learn Danish: Historikeren besøgte arkivet idet hun ville undersøge originalen. - The historian visited the archive, as she wanted to examine the original.

While fordi simply states a direct cause, idet is a more formal conjunction that translates to "as," "since," or "in that." It connects the two actions smoothly, framing her desire to examine the original as the underlying context or justification for her visit.

Could idet also mean "while" or "just as" in other contexts?

Yes! Idet is frequently used as a temporal conjunction to mean "just as" or "exactly while" an action is happening. In this specific sentence, however, it functions causally to explain why she visited the archive.

Since idet introduces a subordinate clause, where would we put an adverb like ikke (not)?

In Danish subordinate clauses, central adverbs like ikke must be placed before the first verb. If she did not want to examine the original, the clause would follow this strict word order: idet hun ikke ville undersøge originalen.

Why is there no comma before idet in this sentence?

Danish has two accepted comma systems. The traditional rules require a comma before all subordinate clauses (arkivet, idet). However, the newer system recommended by the Danish Language Council omits the start comma before subordinate clauses. Both styles are perfectly correct.