4.2 Active/Passive Voice & Sentence Correction
Key Takeaways
- Passive form = object becomes subject + correct be-form for the tense + past participle (V3) + optional by-agent
- Continuous passives use being + V3; perfect passives use been + V3; modals use modal + be + V3
- Sentence correction priorities: agreement, tense consistency, voice logic, modifier placement, and parallel structure
- Dangling participles fail when the implied doer is not the grammatical subject of the main clause
- Keep voice transformations meaning-true: do not change tense category, modality, or number while converting
4.2 Active/Passive Voice & Sentence Correction
Quick Answer: To form the passive, make the object the new subject, insert the matching form of be, use the past participle (V3), and optionally add by + agent. Sentence correction then checks that tense, agreement, modifiers, and parallel structure remain intact.
Voice and sentence-correction items appear throughout Intermediate English papers for PAF technical cadet selection. They test whether you can transform structure without distorting meaning and spot the single grammatical fault in an otherwise plausible sentence.
Active vs Passive — Core Idea
- Active: The subject does the action. Technicians inspected the landing gear.
- Passive: The subject receives the action. The landing gear was inspected by technicians.
Use passive when the doer is unknown, unimportant, or deliberately de-emphasized, or when the object is the topic of the sentence (common in technical reports: The fault was isolated within minutes).
Transformation Checklist
- Identify object of the active verb → it becomes the passive subject.
- Keep the same tense category; only change the verb shape.
- Insert the correct be-form (is, am, are, was, were, be, being, been).
- Change the main verb to V3 (past participle).
- Move the original subject to a by-phrase if needed; omit it when obvious or irrelevant.
Passive Voice Conversion Master Table
| Tense / Form | Active Pattern | Passive Pattern | Example |
|---|---|---|---|
| Simple Present | V1 / V1+s | is/am/are + V3 | Crews service jets → Jets are serviced by crews. |
| Present Continuous | is/are + V-ing | is/are + being + V3 | They are calibrating the compass → The compass is being calibrated. |
| Present Perfect | has/have + V3 | has/have + been + V3 | QA has cleared the batch → The batch has been cleared. |
| Simple Past | V2 | was/were + V3 | The board announced results → Results were announced. |
| Past Continuous | was/were + V-ing | was/were + being + V3 | They were towing the aircraft → The aircraft was being towed. |
| Past Perfect | had + V3 | had + been + V3 | They had sealed the bay → The bay had been sealed. |
| Simple Future | will + V1 | will + be + V3 | Command will issue orders → Orders will be issued. |
| Modal | can/must/should + V1 | modal + be + V3 | You must wear PPE → PPE must be worn. |
| Going to | is going to + V1 | is going to + be + V3 | They are going to scrap the part → The part is going to be scrapped. |
Verbs That Rarely Passivize Well
Intransitive verbs (arrive, happen, sleep, exist) have no object, so they cannot form a true passive. Linking-verb patterns (become, seem, remain) also resist standard passive conversion. If no object exists, the exam answer is usually “cannot be changed into passive” or an active rewrite.
Agent Prepositions Beyond by
Most agents use by, but some passives prefer other prepositions in fixed patterns:
- interested in, known to, surprised at, covered with, made of / from
- Example: The fuselage skin is made of aluminum alloy. (material)
- Example: Paper is made from wood pulp. (transformed source)
Sentence Correction — What Examiners Target
Treat each stem as a hunt for one dominant error class.
1. Agreement Faults
- Wrong: The list of deferred defects were reviewed.
- Right: The list of deferred defects was reviewed.
2. Tense / Sequence Faults
- Wrong: The manual stated that fuel density decreases with temperature rise, and the trainee copies that note yesterday.
- Right: keep scientific present in the reported fact, but use past for the finished copying action: …and the trainee copied that note yesterday.
3. Voice Logic Faults
Do not mix active and passive awkwardly in the same idea chain.
- Awkward: The inspector checked the seals and the leaks were noted by him.
- Better: The inspector checked the seals and noted the leaks. (consistent active)
- Or fully passive if agency is unimportant: The seals were checked and the leaks were noted.
4. Modifier / Participle Placement
A participial phrase must modify the grammatical subject that follows.
- Dangling: Walking across the apron, the jet blast nearly knocked the cadet down. (implies the jet blast was walking)
- Correct: Walking across the apron, the cadet was nearly knocked down by jet blast.
- Correct: As the cadet walked across the apron, jet blast nearly knocked him down.
5. Parallel Structure
Items in a list or comparison must share the same grammatical form.
- Wrong: The course emphasizes reading, to write reports, and grammar drills.
- Right: The course emphasizes reading, writing reports, and drilling grammar.
6. Double Negatives and Redundancy
- Wrong: He could not hardly hear the radio call. → He could hardly hear…
- Wrong: Return back to the hangar → Return to the hangar
- Wrong: Discuss about the failure → Discuss the failure
High-Frequency Correction Patterns (PAF Style)
| Fault Type | Incorrect Stem Fragment | Corrected Form |
|---|---|---|
| Preposition | prefer jet engines than props | prefer jet engines to props |
| Article | She is a honest officer | She is an honest officer |
| Conditional | If he will arrive early, we start | If he arrives early, we will start |
| Relative pronoun | The bay who stores tools… | The bay which/that stores tools… |
| Degree | This alloy is more stronger | This alloy is stronger |
| Infinitive/gerund | avoid to use damaged tools | avoid using damaged tools |
| Countability | many informations | much information / many pieces of information |
| Voice tense drift | Active present → passive past | Keep the same tense category when converting |
Exam Method (60-Second Drill)
- Read for meaning — what is the sentence trying to say?
- Bracket the subject and finite verb — check agreement and tense.
- If voice is tested, rewrite mentally using the master table; reject any option that changes tense or modality.
- Scan openings for dangling -ing phrases and misplaced only / nearly / almost.
- Check lists for parallelism and remove redundant words.
Mastering voice tables plus this five-step correction drill covers the structural half of the PAF AE Initial English requirement at FSc standard.
Choose the correct passive form: "Technicians are replacing the damaged actuator."
Which sentence is grammatically correct?
"Safety goggles must _____ in the machine shop at all times."
Identify the best correction: "The inventory of torque wrenches were checked before the shift began."