Is this sentence active or passive the custodian repaired the classroom door

This sentence is in active voice

A "by" would signal passive voice, such as "The classroom door was repaired by the custodian."

Common/frequent active voice follows this structure: Subject, verb, then object

1. canadian → ned land  2. resolving action → denouement3. narrator of twenty thousand leagues under the sea → pierre aronnax  4. novel of manners → social class   5. planned action → plot  6. samuel pepys → diary  7. omniscient; first-person, limited → point of view  8. ivanhoe → historical novel  9. robinson crusoe → novel of incident  10. abstract idea → theme of novel