Passive vs. Impersonal 'se

There are two main ways we use se here.

The first is the Passive se (Partícula Apassivadora).

In this version, the object of the sentence becomes the subject.

If you say Vendem-se casas, the houses are being sold.

The houses are the subject, so the verb must agree.

The second is the Impersonal se (Índice de Indeterminação do Sujeito).

Here, we don't know who is doing the action.

It is like saying "one does" or "people do" in English.

In this case, the verb is always singular.

It is like a stubborn mule that refuses to change.

Understanding the verb type is the secret key here.

1. 1To master this, follow these three simple steps:
2. 2Identify if the verb is Transitive Direct (VTD).
3. 3These verbs take an object without a preposition.
4. 4Examples include vender, comprar, or fazer.
5. 5If it is VTD, use the Passive se pattern.
6. 6Pattern: [Verb] + se + [Subject].
7. 7The verb must agree with the subject in number.
8. 8If the verb has a preposition (VTI) or is Intransitive (VI).
9. 9Examples include precisar de, confiar em, or viver.
10. 10Use the Impersonal se pattern.
11. 11Pattern: [Verb in 3rd Person Singular] + se + [Prepositional Phrase].
12. 12The verb never, ever changes to plural here.

Use the Passive se when the focus is on the result.

It is perfect for real estate ads or business services.

Consertam-se relógios (Watches are repaired) sounds very professional.

Use it when the 'who' is less important than the 'what'.

Use the Impersonal se when talking about general habits.

It is great for travel tips or social observations.

Vive-se bem em Portugal (One lives well in Portugal).

It is also useful for job advertisements.

Precisa-se de novos talentos (New talent is needed).

This keeps the tone formal and objective in interviews.

It makes you sound like a sophisticated, fluent speaker.

Do not use these patterns if you want to be specific.

If you know exactly who did the action, use the active voice.

Instead of Vende-se o carro, say João vendeu o carro.

Avoid using se if the sentence becomes too clunky.

Sometimes the analytical passive (ser + participle) is clearer.

A casa foi construída em 1990 is often better than Construiu-se a casa.

Also, avoid mixing these up in the same paragraph.

Consistency is your best friend in Portuguese writing.

If you start formal, stay formal until the end.

The biggest trap is the 'Plural Temptation'.

Many people see a plural word and want to pluralize the verb.

Tratam-se de problemas is a very common mistake.

Because de is there, the verb must stay singular: Trata-se de.

Think of the preposition de as a shield.

It protects the verb from the plural influence of the noun.

Another mistake is forgetting agreement in the passive voice.

Aluga-se apartamentos is technically wrong in formal Portuguese.

Since apartamentos is plural, you need Alugam-se apartamentos.

It is like matching your shoes to your belt.

It just looks better when they match up correctly.

Don't confuse these with Reflexive se.

Reflexive means someone is doing something to themselves.

Ele se barbeia (He shaves himself) is not passive.

In reflexive sentences, the person is both the doer and receiver.

In our passive/impersonal patterns, the doer is hidden or irrelevant.

Also, distinguish this from the 'Reciprocal se'.

Eles se abraçaram (They hugged each other) involves two active people.

Passive se is about things being done to objects.

Impersonal se is about a mysterious, general 'someone'.

Keep these three 'se' categories in separate mental boxes.