From active to passive...
Angry penguins |
attack |
my sister.
Onderwerp (S) lijdend voorwerp (O)
1. Direct object (Lijdend voorwerp) moves to the front of the sentence, i.o.w. becomes the subject of the new sentence.
2. Check in what tense the sentence is written, in order to determine the helping verb.
Present tense: add am / is / are | Past tense: add was / were
3. replace tghe main verb with its past participle
My sister is attacked (by angry penguins // by zombies).