Listen to this interesting story about Filip Vukša, a modest Belgrade hero, and try to do the following exercises dedicated to the verb forms in active and passive voice in Serbian.
a. Exercise 1 - filling in the gaps with the appropriate verb form in active voice.
b. Exercise 2 - turning the verbs which were in the active voice from into passive voice.
For some more exercises about the passive voice verb forms (trpni glagolski pridevi), here come two drills:
a. Lakša vežba
b. Teža vežba