Saksóknarinn efast um að vitnisburðurinn sé sannur.
The prosecutor doubts that the testimony is true.
Breakdown of Saksóknarinn efast um að vitnisburðurinn sé sannur.
vera
to be
um
about
að
that (conjunction)
sannur
true
Questions & Answers about Saksóknarinn efast um að vitnisburðurinn sé sannur.
Why is sé used here instead of the regular present tense er?
The verb efast (to doubt) expresses uncertainty. In Icelandic, verbs of doubt and denial—like efast um að and neita því að—trigger the subjunctive mood in the clause that follows them. Because of this rule, we must use the present subjunctive sé rather than the indicative er.
Why is the preposition um included before að? Can I just say efast að?
You cannot drop um. In Icelandic, the verb efast pairs specifically with the preposition um to mean "to doubt". When followed by an að clause, the preposition must stay, creating the fixed phrase efast um að (literally "doubts about that").
If we changed this sentence to the past tense ("The prosecutor doubted..."), how would the verbs change?
The main verb would become the past tense efaðist. Because the main verb would now be in the past, the subjunctive verb in the next clause must also shift to the past subjunctive, becoming væri. The full sentence would be: Saksóknarinn efaðist um að vitnisburðurinn væri sannur.
Is efast a middle-voice verb? What is its active form?