In the following question, a sentence has been given in Active/Passive Voice.…

Concept

When converting a sentence from Active to Passive voice, the object of the active sentence becomes the subject of the passive sentence, and the original subject becomes the agent introduced by ‘by’. Crucially, the tense of the active sentence must be preserved in the passive form — a Simple Past active sentence (subject + V2 + object) converts to a Simple Past passive sentence (object + was/were + V3 + by + subject), never to a future or modal form.

Application

1. Identify the components: subject = ‘the teacher’, verb = ‘scolded’ (Simple Past, the V2 form of ‘scold’), object = ‘Mary’.

2. Swap positions: the object ‘Mary’ moves into the subject position, and ‘the teacher’ becomes the agent introduced by ‘by’.

3. Match the tense: since the active verb is Simple Past, the passive helping verb must also be Simple Past — ‘was’ (matching the singular subject ‘Mary’) followed by the third form of the verb, ‘scolded’.

4. Retain the rest of the sentence unchanged: ‘for not submitting her homework on time.’

5. Combine the parts: ‘Mary was scolded by the teacher for not submitting her homework on time.’

Cross-check

Converting this passive sentence back to active recovers subject ‘the teacher’ + verb ‘scolded’ + object ‘Mary’, which reproduces the original sentence exactly — confirming the tense and structure are correct. A future-tense passive (‘will be scolded’) or a modal passive (‘should be scolded’) would each introduce a tense or meaning that is absent from the original Simple Past sentence.