Active and Passive Voice

Lesson 3: When to Use the Passive Voice

Lesson: 3 of 7 | Level: 🟠 Intermediate — 🟣 Upper-Intermediate

1. Lesson Overview

Knowing how to form the passive voice is one skill. Knowing when to use it — and when not to — is quite another, and it is the more important of the two. The passive is not simply an alternative way of expressing the same information as the active. It is a deliberate communicative choice that changes the perspective, the emphasis, the focus, and sometimes the tone of a sentence. Using it well requires understanding not only the grammatical rules but the communicative principles that govern its use across different contexts and registers.

This lesson examines every major context in which the passive voice is used — from the most elementary to the most advanced — and presents as comprehensive a set of rules as possible for when to choose the passive over the active, and when to choose the active over the passive. The Usage in Context section is particularly extensive in this lesson — it is designed to serve as a reference that learners and teachers can return to throughout their use of the course.

Objectives

By the end of this lesson, you will be able to:

• Identify all the main contexts in which the passive voice is used
• Apply the principles governing the choice between active and passive voice
• Use the passive appropriately across academic, scientific, journalistic, formal, and everyday contexts
• Understand when the active is preferred and why

2. Core Content

A. The Unknown Agent

The most fundamental reason for using the passive is that the agent of an action is unknown — the speaker or writer does not know who performed the action and therefore cannot name them.

For example:

The monitoring equipment was damaged during the storm — no one was present at the station at the time. Several files appear to have been deleted from the server, but it is not yet clear who is responsible.

In both sentences, using the active would require naming an agent that is unknown — which is not possible. The passive allows the action to be described without specifying who performed it.

B. The Unimportant Agent

When the agent is known but unimportant — when naming them adds nothing to the point being made — the passive allows the agent to be omitted and the focus to rest on the action and its result.

For example:

Hydrothermal vents were first observed in 1977 on the floor of the Pacific Ocean. (who observed them — scientists aboard the Alvin — is understood and not the point) The data is collected at hourly intervals and transmitted automatically to the research vessel. (the automated system performs these actions — naming it adds nothing)

C. The Obvious Agent

When the agent is so obvious from context that naming them would be redundant, the passive removes the unnecessary information and focuses the sentence on the action.

For example:

The samples were analysed at three independent laboratories. (scientists analysed them — obvious) The findings will be published next month. (the research team will publish them — obvious) Students are required to submit all work by the published deadline. (the institution requires this — obvious)

D. Foregrounding the Patient

One of the most important and most nuanced reasons for using the passive is to foreground the patient — to make the person or thing receiving the action the grammatical subject and therefore the primary focus of the sentence.

For example:

Darwin proposed the theory of natural selection. (focus on Darwin — what he did) The theory of natural selection was proposed by Darwin. (focus on the theory — what it is and where it came from)

Scientists have studied coral reefs extensively for more than a century. Coral reefs have been studied extensively for more than a century. (the reefs are the topic — not the scientists)

This use of the passive is particularly important in academic and scientific writing — where the object of study is typically the primary topic, not the researchers who study it.

E. Maintaining Topic Continuity

In extended writing, one of the most important functions of the passive is to maintain topic continuity — keeping the same grammatical subject across a series of sentences, even when the actions described involve that subject as a patient rather than as an agent.

For example:

The Amazon basin is one of the most biodiverse regions on Earth. It was formed over millions of years by the convergence of numerous river systems draining the South American continent. It has been studied by biologists and ecologists for more than two centuries. It is now under serious threat from deforestation, agricultural expansion, and climate change. It must be protected if the extraordinary diversity of species it contains is to be preserved for future generations.

Every sentence has the Amazon basin (or a pronoun referring to it) as its grammatical subject — the passive in sentences two, three, and four makes this continuity possible. Without the passive, the writer would be forced to change the subject each time a new agent was introduced, disrupting the thematic flow of the paragraph.

F. Achieving End Focus

English places the most important and most informative element of a sentence at its end — a principle known as end focus or end weight. The passive gives writers precise control over what appears at the end of a sentence, and therefore what receives the greatest emphasis.

For example:

In 1977, hydrothermal vent communities were discovered by scientists aboard the research vessel Alvin. (end focus on the discoverers) In 1977, by scientists aboard the research vessel Alvin, hydrothermal vent communities were discovered. (awkward — end focus poorly managed) Hydrothermal vent communities were discovered in 1977. (end focus on the date — clean and effective)

The passive allows the writer to place the agent at the end (for emphasis on who did something), in the middle (for a neutral mention), or to omit it entirely (when the action and its result are what matter).

G. Scientific and Academic Writing — The Impersonal Passive

In academic and scientific writing, the passive is conventionally used to describe methods, procedures, materials, and findings in an objective, impersonal, and replicable way. This convention — sometimes called the impersonal passive — presents research as a systematic process rather than as the personal acts of individual researchers.

For example:

Samples were collected from twelve sites across the vent field between January and March. The data was processed using the standard statistical methodology described in the appendix. Temperature readings were recorded at five-minute intervals throughout the monitoring period. The correlation between ocean warming and bleaching frequency was assessed using linear regression analysis.

In all four sentences, the passive presents the procedures as objective and impersonal — any competent researcher following the same methods would produce the same results. The active equivalents — we collected samples, we processed the data — would imply that the results depend on the personal involvement of the specific researchers, which is not the impression academic writing typically seeks to create.

H. Journalistic and News Writing

In journalism, the passive is used to report events objectively — presenting what happened without assigning responsibility, or when the identity of the agent is unknown, unconfirmed, or deliberately withheld.

For example:

Three researchers were injured during the expedition when the monitoring platform collapsed. The data was leaked to the press before the official publication date. A previously unknown species has been identified in the deep waters of the southern Indian Ocean.

In news writing, the passive is also used in headlines — where brevity is paramount and the agent is either obvious or unimportant.

New species discovered in deep ocean. Research station damaged by storm. Climate targets missed for third consecutive year.

I. Formal, Legal, and Official Contexts

In formal, legal, and official writing, the passive is widely used to express requirements, instructions, obligations, and prohibitions — presenting them as impersonal rules rather than as personal commands from an identified authority.

For example:

All data must be submitted to the central archive within thirty days of collection. Applications are required to be submitted in the prescribed format. Samples must not be removed from the controlled environment without prior written authorisation. The results are expected to be made available to the scientific community within twelve months of collection.

The passive in these contexts removes the personal element — the rules apply universally, regardless of who is issuing them or who is required to comply.

J. Avoiding the Assignment of Responsibility

In diplomatic, political, and institutional contexts, the passive is used to describe actions without assigning responsibility — whether to avoid blame, to maintain neutrality, or to be tactful.

For example:

Errors were made in the original analysis — errors that have since been identified and corrected. The data was misinterpreted in the preliminary report, leading to conclusions that have since been revised. It was decided that the project would be terminated at the end of the current funding cycle.

In all three sentences, the passive conceals or avoids specifying who made the errors, who misinterpreted the data, or who made the decision — a deliberate and sometimes controversial use of the construction.

K. Describing Processes and Systems

The passive is used extensively in technical, scientific, and instructional writing to describe processes, systems, and procedures — where the focus is on what happens in the process rather than on who or what makes it happen.

For example:

Carbon dioxide is absorbed by the ocean, where it reacts with water to form carbonic acid. Light is converted into chemical energy through the process of photosynthesis, which takes place in the chloroplasts of plant cells. Seawater is pumped through the filtration system, where particles are removed and the purified water is returned to the tank.

L. Expressing General Truths and Universal Statements

The passive — particularly the simple present passive — is used to express general truths and universal statements that apply regardless of who performs them.

For example:

New species are discovered at an accelerating rate as deep-sea exploration technologies improve. Scientific theories are accepted not on the basis of authority but on the basis of evidence that can be independently verified and replicated. Languages are shaped by the communities that speak them and change over time in response to social, cultural, and technological developments.

M. In Reported and Indirect Speech**

The passive is frequently used in reported speech — particularly with reporting verbs such as say, report, claim, believe, know, think, and suggest — to present claims and views impersonally. This use is examined in detail in Lesson 5.

For example:

It is widely believed that the deep ocean contains many species that have never been observed. It has been reported that the monitoring network was damaged during the seismic event. It is claimed that the preliminary findings have been misrepresented in recent press coverage.

N. In Instructions and Procedural Writing

The passive is used in instructions, recipes, manuals, and procedural texts to describe what should be done — presenting each step as an objective process rather than a personal command.

For example:

The sample is placed in the centrifuge and spun at 3,000 rpm for twenty minutes. The instrument is calibrated before each use by adjusting the baseline reading to zero. The data is entered into the system and cross-referenced against the archive before the analysis begins.

O. When Not to Use the Passive

Equally important is understanding when the passive is inappropriate and the active is preferable.

When the agent is important and relevant

If the agent is the primary focus of the sentence — if who performed the action is important — the active is more appropriate.

Darwin proposed the theory of natural selection after years of careful observation. (Darwin is the subject — the active foregrounds his role)

When the active is more direct and natural

In informal and conversational English, the passive can sound unnecessarily formal, pompous, or evasive. The active is generally preferred in spoken English and in informal writing.

We collected the samples yesterday. (direct and natural) The samples were collected by us yesterday. (passive — unnecessarily formal in this context)

When the passive creates ambiguity

If omitting the agent creates ambiguity about who performed the action — if the reader cannot infer who the agent is — the active is clearer.

The report was revised three times. (passive — who revised it? ambiguous if multiple parties are involved) The research team revised the report three times before submission. (active — clear and unambiguous)

When overuse creates a monotonous style

Excessive use of the passive — particularly in academic writing — produces a monotonous and impersonal style that obscures meaning and reduces clarity. A mix of active and passive constructions produces more effective prose.

3. Usage in Context

• Use the passive when the agent is unknown — the action can be described without specifying who performed it.

The monitoring equipment was vandalised during the night — there were no witnesses and no camera footage. Several core samples appear to have been mislabelled at some point during the collection process — the error has not yet been traced to its source.

• Use the passive when the agent is unimportant and naming them would add nothing to the sentence.

The samples were collected at twelve sites and stored at −20°C before being transported to the laboratory. The findings have been replicated at three independent institutions, confirming the robustness of the original methodology.

• Use the passive when the agent is obvious from context and mentioning them is redundant.

New monitoring stations will be installed during the next expedition to improve spatial coverage of the vent field. (installed by the research team — obvious) Students are required to submit all coursework by the published deadline. (required by the institution — obvious)

• Use the passive to foreground the patient — placing the person or thing receiving the action in the subject position for maximum attention and emphasis.

The theory of natural selection was proposed by Darwin in 1859 and has been confirmed by more than a century of accumulated scientific evidence. Hydrothermal vents were discovered in 1977 — a finding that permanently transformed our understanding of the conditions necessary for life on Earth.

• Use the passive to maintain topic continuity across a series of sentences — keeping the same grammatical subject even when the topic is described as a patient.

The Amazon basin is one of the most ecologically significant regions on Earth. It was formed over millions of years by geological and hydrological processes. It has been studied by scientists for more than two centuries. It is currently threatened by deforestation at an unprecedented rate. It must be protected if its extraordinary biodiversity is to survive.

• Use the passive to achieve end focus — placing the most important element at the end of the sentence where it receives maximum emphasis.

The first hydrothermal vent community was observed in 1977 by scientists aboard the Alvin. (end focus on the discoverers) In 1977, the first hydrothermal vent community was observed. (end focus on the date) The first hydrothermal vent community was discovered — a finding that would change everything. (end focus on the significance)

• Use the passive in academic and scientific writing to describe methods, procedures, and findings in an objective and impersonal way.

Samples were collected from twelve sites, stored at −20°C, and subsequently analysed at three independent laboratories using the methodology described in Section 3. Temperature readings were recorded at five-minute intervals over a continuous period of eighteen months, producing a data set of more than 189,000 individual observations.

• Use the passive in news reporting and journalism to describe events objectively — particularly when the identity of the agent is unknown, unconfirmed, or not the focus of the report.

Three researchers were injured when the monitoring platform collapsed during a routine maintenance operation. A new species of deep-sea fish has been identified by marine biologists working in the southern Indian Ocean.

• Use the passive in formal, legal, and official writing to express requirements and obligations impersonally.

All expedition members are required to complete the mandatory safety training before departure from port. The data must be submitted to the central archive in the prescribed format within thirty days of collection.

• Use the passive to avoid assigning responsibility — in diplomatic, political, and institutional contexts where neutrality or tact is required.

Errors were made during the initial phase of the project — errors that have since been identified and corrected. It was decided that the funding for the programme would not be renewed beyond the current cycle.

• Use the passive to describe processes, systems, and sequences of steps — where the focus is on what happens rather than on who makes it happen.

Carbon dioxide is absorbed by the ocean at the surface and transported to the deep ocean by thermohaline circulation. The sample is placed in the centrifuge, which spins it at 3,000 rpm for twenty minutes, separating its components by density.

• Use the passive in reporting verb constructions — it is believed that, it has been reported that, it is widely known that — to present claims and views without attributing them to a specific source.

It is widely believed that the deep ocean contains many species that have never been observed or described by science. It has been suggested that the rate of deep-sea species loss may already be accelerating as a result of warming and acidification.

• Use the passive in instructions and procedural texts to present each step as an objective process.

The solution is prepared by dissolving the compound in distilled water at a ratio of 1:10 by volume. The instrument is calibrated by adjusting the zero offset until the baseline reading falls within the specified tolerance.

• Use the passive when the by-phrase adds important contrastive or identifying information — naming who performed the action is significant.

The theory was proposed by Wegener — not by the scientific establishment that rejected it for forty years. The discovery was made by a graduate student on her first expedition — not by the senior researchers who had been working in the field for decades.

• Use the passive with modal verbs to express necessity, possibility, and obligation about actions without specifying who is responsible for performing them.

All data must be archived in a durable and accessible format within thirty days of collection. The samples should be stored at a constant temperature to prevent degradation before analysis. The findings may be published before the end of the year if the peer review process proceeds without delay.

• Use the active — not the passive — when the agent is the primary focus and their identity is important.

Darwin proposed the theory — a fact that should not be obscured by the passive. (active — Darwin’s role is the point) Wallace independently arrived at the same conclusion — a remarkable coincidence that forced Darwin’s hand. (active — Wallace’s independent achievement is the focus)

• Use the active — not the passive — in informal speech and writing, where the passive would sound unnecessarily formal or awkward.

We collected the samples on Monday and sent them to the laboratory on Tuesday. (natural and direct) The samples were collected by us on Monday and were sent to the laboratory on Tuesday. (passive — unnecessarily formal and slightly awkward)

• Use the active — not the passive — when the passive would create ambiguity by omitting a necessary agent.

The report was revised before submission. (passive — who revised it? may be ambiguous) The research team revised the report three times before submission. (active — clear and unambiguous)

• Avoid overusing the passive — a mix of active and passive constructions produces more effective and more readable prose than a reliance on either alone.

Effective academic writing uses the passive strategically — for methods, procedures, and findings — while using the active for argument, interpretation, and narrative.

4. Common Errors and Corrections

5. Lesson Mastery

After completing this lesson, you should now be able to:

    ✅ Identify all the main contexts in which the passive voice is used

    ✅ Apply the principles governing the choice between active and passive voice

    ✅ Use the passive appropriately across academic, scientific, journalistic, formal, and everyday contexts

    ✅ Understand when the active is preferred and why