Questions & Answers about Hún vaknaði úr dáinu.
In Icelandic, vakna already means wake up / awaken. So Hún vaknaði naturally means she woke up.
English often uses a particle like up, but Icelandic does not need one here. You can sometimes see vakna upp, but plain vakna is the normal basic verb.
Vaknaði is the 3rd person singular past tense of vakna.
So:
- vakna = to wake up
- vaknaði = woke up
It matches hún (she), which is third person singular.