Select the option that expresses the given sentence in passive voice.
The mechanic at the petrol pump had changed the flat tyre before the rain started.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → The flat tyre had been changed by the mechanic at the petrol pump before the rain started.
Passive of the past perfect:
| Change | Active | Passive | Why |
|---|---|---|---|
| Object becomes subject | the flat tyre | The flat tyre | The flat tyre receives the action, so it becomes the subject. |
| Tense kept | had changed | had been changed | “Had changed” is in the past perfect, so the passive stays in the past perfect: had been + past participle (V3). |
| Agent (by ...) | The mechanic at the petrol pump | by the mechanic at the petrol pump | The mechanic is named, so the doer comes after “by”. |
| Full sentence | The mechanic at the petrol pump had changed the flat tyre before the rain started. | The flat tyre had been changed by the mechanic at the petrol pump before the rain started. |
Other past perfect verbs work the same way: had sold → had been sold, had written → had been written. Example: The shopkeeper had sold all the kites before Sankranti. → All the kites had been sold by the shopkeeper before Sankranti.
Why the Other Options are Incorrect?
Option 1: The flat tyre was changed by the mechanic at the petrol pump before the rain started. — Incorrect. “Was changed” is the simple past. The active “had changed” is the past perfect.
Option 2: The flat tyre had changed by the mechanic at the petrol pump before the rain started. — Incorrect. The word “been” is missing. Without it, the verb is still active.
Option 3: The flat tyre has been changed by the mechanic at the petrol pump before the rain started. — Incorrect. “Has been changed” is the present perfect. The active “had changed” is the past perfect.