Breakdown of Poljin vaurioitui, kun pyörä kaatui.
Questions & Answers about Poljin vaurioitui, kun pyörä kaatui.
Vaurioitui is the 3rd person singular past tense of vaurioitua, which means to get damaged or to become damaged.
So:
- vaurioitua = to get damaged
- vaurioitui = got damaged / became damaged
It is not a passive form. The subject is poljin, so the sentence says that the pedal was the thing that became damaged.
Poljin is the subject of the main clause, so it appears in the nominative singular, which is the basic dictionary form.
In Poljin vaurioitui:
- poljin = the pedal
- vaurioitui = got damaged
This works much like English: The pedal got damaged.
Because the pedal is the thing that underwent the change, Finnish uses it as the subject, not as an object.