Voice is a grammatical category that tells you who is doing the action in a sentence. That is the entire concept — nothing more complicated than that.
In active voice, the subject does the action:
The chef cooked the meal.
The chef (subject) is cooking. Subject is busy, subject is the actor.
In passive voice, the subject receives the action:
The meal was cooked by the chef.
Now "the meal" is the subject, but it is not doing anything — it is being acted upon. The original doer (the chef) gets pushed to the end, usually with "by".
Think of it like this: imagine a CCTV clip. Active voice is the camera pointing at the person who is acting. Passive voice is the camera pointing at the object being affected, and you only get to see the actor as a footnote in the corner of the frame.
Why does SSC MTS test this? Because voice change requires you to handle tenses accurately under time pressure. The question types you will see are:
The trap the exam sets is consistent: students get the tense wrong when converting. They recognise the structure but then pick the wrong auxiliary. The difference between was identified and is identified can cost you a mark. This guide will build a reflex for that exact decision.
One important rule before we go further: not every sentence can be converted to passive voice. A sentence must have a transitive verb (a verb that takes an object) for passive conversion to be possible. She sleeps has no object — there is nothing to become the subject in passive. You cannot convert it.
Here is the conversion formula in one line:
Active:
Subject + Verb (appropriate tense) + ObjectPassive:Object → Subject + Auxiliary (be-form) + Past Participle + by + Old Subject
The key is this: when you convert, the tense stays the same, but it is now expressed through the be-form auxiliary, not through the main verb directly. The main verb always becomes the past participle (V3) in passive.
This table is the backbone of every voice question. Memorise it column by column.
| Tense | Active Structure | Passive Structure |
|---|---|---|
| Simple Present | takes | is/are taken |
| Simple Past | took | was/were taken |
| Simple Future | will take | will be taken |
| Present Continuous | is/are taking | is/are being taken |
| Past Continuous | was/were taking | was/were being taken |
| Present Perfect | has/have taken | has/have been taken |
| Past Perfect | had taken | had been taken |
| Future Perfect | will have taken | will have been taken |
| Modal (can/must/should etc.) | can take | can be taken |
Look at the pattern in the right column. Every passive structure contains a form of "be" (is, are, was, were, been, being) placed before the past participle. That is the signature of passive voice.
When the old object becomes the new subject, object pronouns (me, him, her, us, them) become subject pronouns (I, he, she, we, they). And when the old subject is moved to the "by" phrase, it becomes an object pronoun.
| Active Subject → "by" phrase | Active Object → New Subject | |---|---| | I → by me | me → I | | He → by him | him → he | | She → by her | her → she | | We → by us | us → we | | They → by them | them → they | | You → by you | you → you |
This is where most SSC MTS errors happen. Questions have a different structure and you need to preserve the question format in the passive.
Yes/No questions:
Did she write the letter?Was the letter written by her?The auxiliary did (simple past) becomes was/were in passive. The sentence remains a question.
Wh- questions:
How does the detective identify the culprit?How is the culprit identified by the detective?The Wh-word (how, when, where, why, what, who) stays at the front. Then you apply the normal passive formula for the rest of the sentence. The auxiliary matches the tense — here does identify (simple present) becomes is identified.
Past Perfect questions:
Had they submitted the report?Had the report been submitted by them?Look — the word order in the passive question: Had + new subject + been + V3 + by + old subject. The had stays at the front because it is still a question.
Negatives are straightforward — the negative particle stays with the auxiliary.
Many people didn't like your novel.Your novel wasn't liked by many people.Didn't (past negative) becomes wasn't — same tense, negative preserved.
You can omit the "by" phrase when:
The window was broken.He was arrested. (clearly by police)The road is being repaired.In SSC MTS, if all the options include "by them" or "by her", you keep it. If an option drops it and still makes grammatical sense, it can be correct — but match what the options give you.
Sometimes the question asks you to simply identify the voice. The quick check:
be-form + V3? → Passive voice.If you see unfolds, seek, discover — all simple tense verbs with the subject performing the action — that is active voice.
When converting any sentence to passive, think SAPS:
Active: He wrote a letter. → Apply SAPS → A letter (S) was (A) written (P) by him (S).
This pattern works for every tense without needing to remember individual rules. Standard approach: recall the full tense table (20-30 seconds). SAPS: identify the slot and fill it in (8-10 seconds).
In passive voice, the be-form auxiliary carries all tense information. Check only the auxiliary to verify the tense:
is/are → simple present passivewas/were → simple past passivehas/have been → present perfect passivehad been → past perfect passivewill be → simple future passiveis/are being → present continuous passiveWhen you see an option with is published for a sentence that was in simple past, eliminate it immediately — the tense fingerprint is wrong. This eliminates 2-3 wrong options in under 5 seconds, turning a 40-second reasoning question into a 15-second elimination.
For any interrogative sentence conversion, extract this skeleton first:
[Wh-word or blank] + [First auxiliary] + [New subject] + been/being (if needed) + V3 + by + [old subject]
For Had they submitted the report?:
Had, new subject = the report, add been (past perfect), V3 = submitted, old subject = themHad the report been submitted by them?The key insight: Had in past perfect passive always needs been after the new subject. If an option shows Had + subject + submitted (no been), cut it. This eliminates options in 5 seconds vs. constructing the full sentence in 25 seconds.
The most common careless error: picking the wrong be-form because you forget to check whether the new subject is singular or plural.
The National Archives — looks plural, but it is a single institution → singular → preserves in active, is preserved in passive.Several discoveries — plural → have been made.Before writing the passive, pause and ask: is my new subject singular or plural? Then pick is/was/has OR are/were/have accordingly. This 3-second check prevents the most frequent wrong-answer trap in SSC MTS voice questions.
When converting negatives, the not always attaches to the first auxiliary in the passive construction:
didn't like → wasn't liked (not was not been liked)haven't seen → haven't been seen (the not stays with have)hadn't told → hadn't been toldDo not add an extra not or move it to the wrong position. Standard approach: reconstruct the full negative passive from scratch (20 seconds). This pattern: find the first auxiliary, attach not, then add the rest (8 seconds).
When you get a voice transformation question in the exam hall, run through this decision tree in order:
Step 1 — Identify the tense of the original sentence. Look at the main verb and any auxiliaries. Write the tense name mentally: simple past, present perfect, etc.
Step 2 — Identify the type of sentence. Is it a statement, a negative, or a question (yes/no or Wh-)? This determines your output structure.
Step 3 — Apply the SAPS formula. Move the object to the front. Place the correct be-form auxiliary (use the Auxiliary Fingerprint). Place V3. Add "by + old subject" at the end.
Step 4 — Check agreement. Does your new subject agree in number with your auxiliary? Singular → is/was/has been. Plural → are/were/have been.
Step 5 — Eliminate wrong options fast. Scan the options for the correct tense fingerprint (Step 1) and cut everything that uses a different tense auxiliary. Usually one or two options survive — pick the grammatically clean one.
Total time target: 30-45 seconds per question.
Why this question — Tests past perfect passive in an interrogative sentence, the hardest combination.
Solving path — The original sentence: Had they submitted the final report by the time the director arrived? The tense is past perfect (Had + subject + V3). It is a yes/no question. Apply the Question Skeleton: Had + [new subject: the final report] + been + submitted + by them + ... The been is mandatory in past perfect passive — this cuts options A, B (wrong tense), and C (wrong tense). Option D is the only one with Had ... been submitted — correct.
Why this question — Tests simple present passive in a Wh- question. The distractor options mix up is/will/does in the auxiliary position.
Solving path — Active sentence: How does the detective identify the culprit so easily? Tense: simple present (auxiliary does). Wh-word: How stays at front. New subject: the culprit (singular). Auxiliary fingerprint for simple present passive: is. So: How is the culprit identified by the detective so easily? Option C. Cut A (wrong auxiliary do), B (wrong tense will), D (wrong — does cannot appear in passive).
Why this question — Tests passive-to-active conversion. Also tests subject-verb agreement since "The National Archives" is a singular collective noun.
Solving path — Passive: The heritage manuscripts are preserved by the National Archives for future generations. Auxiliary are preserved → simple present tense. Move The National Archives to subject position. It is a single institution (singular) → use preserves. Active: The National Archives preserves the heritage manuscripts for future generations. Option D. Cut A (is preserving — present continuous, wrong tense), B (has preserved — perfect, wrong tense), C (preserved — past, wrong tense).
Why this question — Tests identification of voice without conversion. Tests whether you can identify active voice even when the sentence is complex.
Solving path — Sentence: The narrative unfolds as characters seek to discover who committed the crime. Check the main verbs: unfolds, seek, discover, committed. None of them follow the be-form + V3 pattern that is the signature of passive voice. The subjects are performing all the actions. This is active voice. Option B. "Reflexive voice" and "causative voice" are not standard grammatical categories in this context — eliminate them immediately.
Why this question — Classic simple past conversion. Tests whether you correctly pick was (not is, has been, or had been).
Solving path — Active: She published her new novel last year. Tense: simple past (published). New subject: Her new novel (singular). Auxiliary fingerprint: was. Passive: Her new novel was published last year by her. Option A. The time marker last year also confirms past tense — cut B (is published — present), C (has been published — present perfect), D (had been published — past perfect).
Adding "been" where it does not belong. Simple past passive is was/were + V3, not was/were + been + V3. Writing was been published is wrong. Been appears only in perfect tenses (has been, had been) and present continuous passive (is being).
Forgetting the question structure in interrogative conversions. The passive must remain a question. A common error is writing The culprit is identified by the detective so easily? — the auxiliary is must come before the subject: How is the culprit identified.... The inversion that marks a question must be preserved.
Treating collective nouns as plural. The National Archives, The committee, The government — these are singular entities. They take is/was/preserves, not are/were/preserve.
Ignoring the negative. In negative sentences like Many people didn't like your novel, students sometimes write Your novel was not been liked (wrong) or Your novel wasn't been liked (wrong). The correct form: Your novel wasn't liked. No double auxiliary error.
Changing tense during conversion. The tense of the passive must match the tense of the active. If the active is simple present, the passive must also be simple present. A sentence with does identify converts to is identified, not will be identified or was identified.
Using object pronouns as subjects in the passive. If him becomes the new subject, it must become he. Writing Him was seen by her is wrong. The pronoun must change: He was seen by her.