1. Lesson Overview
In this lesson, you will learn the fundamental difference between active and passive voice.
Voice refers to the way a sentence presents the relationship between the subject, verb, and object.
English uses two voices:
-
Active voice
-
Passive voice
In active voice, the subject performs the action.
Example:
The researcher analysed the data.
In passive voice, the focus shifts to the receiver of the action.
Example:
The data were analysed by the researcher.
Understanding how voice works allows writers to control the focus and emphasis of a sentence, especially in academic and formal writing.
By the end of this lesson, you will be able to:
-
explain the difference between active and passive sentences
-
understand how subjects and objects change position
-
recognise how passive voice changes the focus of a sentence
-
apply the basic formula for forming passive constructions
2. Concept Introduction
Consider the following pair of sentences:
The technician repaired the equipment.
The equipment was repaired by the technician.
Both sentences describe the same event, but the focus is different.
| Sentence | Voice | Focus |
|---|---|---|
| The technician repaired the equipment. | active | the technician |
| The equipment was repaired by the technician. | passive | the equipment |
The passive sentence highlights the object or result, rather than the person performing the action.
3. Core Explanation
Voice changes the grammatical organisation of a sentence, but the meaning remains essentially the same.
Active Voice
In the active voice, the subject performs the action.
Structure:
Subject + Verb + Object
Example:
The scientist conducted the experiment.
| Element | Function |
|---|---|
| scientist | subject |
| conducted | verb |
| experiment | object |
Passive Voice
In the passive voice, the object becomes the grammatical subject, and the verb changes form.
Structure:
Object + form of “be” + past participle (+ by + subject)
Example:
The experiment was conducted by the scientist.
| Element | Function |
|---|---|
| experiment | subject (receiver of action) |
| was conducted | passive verb |
| by the scientist | agent |
4. Rule Table
Active Voice Structure
| Structure | Example |
|---|---|
| subject + verb + object | The researcher analysed the samples. |
Passive Voice Structure
| Structure | Example |
|---|---|
| object + be + past participle | The samples were analysed. |
| object + be + past participle + by + subject | The samples were analysed by the researcher. |
Verb Transformation
| Active Verb | Passive Verb |
|---|---|
| analysed | was analysed |
| repaired | was repaired |
| completed | was completed |
The passive form always uses be + past participle.
5. Usage
1. Active voice focusing on the doer
Example:
The engineer designed the system.
2. Passive voice focusing on the action
Example:
The system was designed by the engineer.
3. Passive voice focusing on the result
Example:
The results were recorded carefully.
4. Passive voice when the doer is unknown
Example:
The equipment was damaged during the experiment.
5. Passive voice in formal writing
Example:
The experiment was conducted under controlled conditions.
6. Signal Words
Passive voice often appears in contexts that emphasise processes, results, or procedures.
| Context | Example |
|---|---|
| scientific writing | The experiment was conducted carefully. |
| procedures | The samples were analysed in the laboratory. |
| reports | The results were recorded accurately. |
| formal writing | The data were collected systematically. |
| instructions | The equipment must be handled carefully. |
7. Special Cases
Agentless Passive
Sometimes the doer of the action is omitted.
Example:
The results were published yesterday.
The sentence focuses on the result, not the person responsible.
Passive Voice in Academic Writing
Passive voice is often preferred when describing procedures or research methods.
Example:
The samples were analysed using specialised equipment.
This structure keeps the focus on the process rather than the researcher.
8. Additional Notes
Although passive voice is useful, excessive use may make writing less direct or less clear.
Example:
Passive:
The report was written by the researcher.
Active:
The researcher wrote the report.
Active voice is often clearer and more direct, especially in everyday communication.
9. Common Errors
⚠ Incorrect passive verb form
Incorrect:
The report was wrote by the researcher.
Correct:
The report was written by the researcher.
Explanation:
Passive voice requires past participle forms.
⚠ Missing auxiliary verb
Incorrect:
The equipment repaired by the technician.
Correct:
The equipment was repaired by the technician.
Explanation:
Passive verbs require a form of “be.”
⚠ Incorrect word order
Incorrect:
Repaired the technician the equipment.
Correct:
The technician repaired the equipment.
Explanation:
Active sentences follow subject + verb + object order.
⚠ Incorrect passive structure
Incorrect:
The experiment conducted by the scientist.
Correct:
The experiment was conducted by the scientist.
Explanation:
Passive voice requires be + past participle.
⚠ Using passive with intransitive verbs
Incorrect:
The event was happened yesterday.
Correct:
The event happened yesterday.
Explanation:
Intransitive verbs cannot form passive voice.
10. Lesson Mastery
After completing this lesson, you should now be able to:
✅ explain the difference between active and passive voice
✅ understand how subjects and objects change position
✅ recognise how passive voice changes the focus of a sentence
✅ apply the basic formula for forming passive constructions