受動態: 正しく使うタイミングと方法

受動態は、文の焦点を「誰が動作をするか」から「誰が・何がその動作を受けるか」へと移します。フォーマルな文章を書くときにも、アカデミックやビジネス英語の中で見分けるためにも、すべての学習者に欠かせない構文です。

What Is Passive Voice?

In an active sentence, the subject performs the action. In a passive sentence, the subject receives the action, and the person or thing doing the action either appears after by or disappears entirely.

Active: "The teacher graded the essays." → Passive: "The essays were graded by the teacher."

The Critical Distinction: Active vs. Passive Voice

This is the choice that shapes the tone of an entire piece of writing, and it's frequently misused in both directions. Active voice is direct, clear, and generally preferred, since it names who is responsible for the action. Passive voice is useful when the doer of the action is unknown, unimportant, or intentionally left out, which is common in scientific writing, news reporting, and formal reports.

Correct "The experiment was conducted in a controlled environment." (the researcher doing it isn't the point)

Incorrect "The ball was thrown by John." (overused passive; active is clearer here: John threw the ball)

How to Form the Passive Voice

Passive voice is built with a form of be plus the past participle of the main verb. The tense of be matches whatever tense the sentence needs:

Tense	Active	Passive
Present simple	She writes the report.	The report is written by her.
Past simple	She wrote the report.	The report was written by her.
Present continuous	She is writing the report.	The report is being written by her.
Present perfect	She has written the report.	The report has been written by her.
Future simple	She will write the report.	The report will be written by her.
Modal	She can write the report.	The report can be written by her.

When to Use Passive Voice

The passive voice is particularly effective across specific real-world contexts and writing scenarios:

Unknown Doer Unknown

When you don't know who performed the action.

Example: "My phone was stolen."

Unimportant Doer Obvious

When the actor is obvious or irrelevant to the reader.

Example: "The building was constructed in 1990."

Formal & Scientific Objective

Maintaining objective focus in research papers and lab reports.

Example: "The samples were tested for contamination."

Emphasizing Results Focus

Highlighting the final outcome over the person who did it.

Example: "The bridge was completed ahead of schedule."

Informal Passive with Get

In everyday spoken English, get often replaces be in passive constructions, especially for unexpected, negative, or sudden events. This form is too informal for academic writing but very common in conversation and casual messages.

Standard Passive (be)	Informal Passive (get)
He was fired last week.	He got fired last week.
My phone was stolen.	My phone got stolen.
She was promoted to manager.	She got promoted to manager.
Two people were injured in the accident.	Two people got injured in the accident.
We were invited to the party.	We got invited to the party.

Grammar Note Use get passive for spoken English and informal writing. Switch to be passive for essays, reports, and exams.

Common Pattern Get passive often carries a sense of something happening to someone unexpectedly: get hurt, get lost, get caught, get stuck, get paid.

Active or Passive? Quick Check

Practice identifying whether a sentence uses active or passive voice:

Sentence	Voice	Why
The chef prepared the meal.	Active	Subject performs the action
The meal was prepared by the chef.	Passive	Subject receives the action
They will announce the results tomorrow.	Active	Subject performs the action
The results will be announced tomorrow.	Passive	Subject receives the action
She got promoted last month.	Passive (get)	Informal passive, subject receives the action

Common Mistakes

Avoid these typical auxiliary verb and participle errors when forming passive structures:

Incorrect	Correct
The report was write by her.	The report was written by her.
The cake baked by my mother.	The cake was baked by my mother.
Mistakes was made.	Mistakes were made.
The report is writing by her.	The report is being written by her.

How Learna AI Teaches Passive Voice?

Learna AI listens for be plus a past participle and checks that the auxiliary matches the intended tense, correcting mismatches like a missing form of be or a main verb left in its base form. It also flags overused passive voice in casual conversation, since active voice usually sounds more natural in everyday speech, and recognizes get passive as a valid informal alternative while noting when formal writing requires the standard be form instead. Learners practicing formal and scientific English with Learna report a 73% improvement in forming the passive voice correctly across different tenses.

Once passive voice feels natural, it connects closely with reported speech, since both structures often appear together in formal writing and news-style reporting.

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