Sophia says: Spot the aorist tense
The aorist tense is a very commonly used past tense in Greek. Notice how it has both an augment before the stem and a sigma between the stem and the person endings. The person endings are different from the tenses you have met previously.
ελυσα I set free (did set free)
ελυσας you set free
ελυσε s/he set free
ελυσαμεν we set free
ελυσατε you (pl) set free
ελυσαν they set free