Impersonal and passive se; generic subjects

What it is

Sometimes the person doing the action doesn’t matter, isn’t known, or is simply "people in general". Portuguese has several ways to leave that person unnamed, and Brazilians choose between them mostly by register:

• passive se: Vendem-se casas. (Houses for sale.)
• impersonal se: Precisa-se de garçons. (Waiters wanted.)
• 3rd-person plural with no subject: Roubaram meu celular. (Someone stole my phone.)
• generic você / a gente: Aqui você paga na saída. (Here you pay at the exit.)
• zero subject in speech: Aqui vende chip? (Do you sell SIM cards here?)

The first two are what you read on signs, in ads, in news and instructions. The last three are what you hear in conversation.

How to form it

Passive se: the verb agrees

With a verb that takes a direct object (vender, alugar, aceitar, consertar), se makes it passive, and the noun after the verb is its grammatical subject. In the written norm, the verb agrees with it:

On real signs you will often see Vende-se casas or Aluga-se quartos. Many speakers feel the noun is an object, and some linguists agree; the form is widespread and the debate is real. Still, school grammar, exams and formal writing expect agreement: Vendem-se casas. In this course we accept the singular in signs and speech, and expect the plural in formal texts.

Impersonal se: always singular

When the verb takes a preposition (precisar de, tratar de, confiar em), has no object at all (viver, trabalhar, comer bem), or is followed by an infinitive (pode fumar), the se is impersonal and the verb is always singular:

Precisam-se de garçons is a hypercorrection: the noun after de can never be the subject.

Where se goes

At the start of a sentence, in writing, se comes after the verb with a hyphen: Aluga-se, Trata-se de. After an "attractor" (não, nunca, já, que, quem), it goes before: Aqui não se pode fumar, Nunca se sabe!, Nunca se venderam tantos ingressos. After other words, Brazilian writing accepts both: Em Florianópolis vive-se bem / se vive bem.

Try a few:

When to use it

Signs and ads use se: Aluga-se, Vende-se, Precisa-se de, Procura-se (wanted / missing), Aceitam-se encomendas, Fazem-se chaves (keys cut).

News and reports use se or the ser passive (pt-g-065): Nunca se venderam tantos carros, Trata-se de um caso raro.

Conversation avoids se in most of these jobs:

• an unknown "they" → 3rd-person plural, no pronoun: Ligaram do banco. Me deram troco errado. Estão construindo um prédio aqui na rua.
• rumours → Dizem que…, Falaram que…
• "anyone, including me" → a gente or você: Em Porto Alegre a gente toma chimarrão o dia inteiro. Nesse restaurante você se serve e paga por quilo.
• rules and questions about what’s possible → zero subject: Pode estacionar aqui? Aqui não pode fumar. Precisa agendar?

Contrasts and traps

• Agreeing vs invariable. Contratam-se professores (no preposition, plural) vs Precisa-se de professores (preposition, singular).
• Never open a sentence with se in writing. Se vende casa is Spanish order; the Portuguese sign is Vende-se casa.
• 3rd-person plural excludes you; a gente includes you. Dizem que é perigoso = people say (not me). A gente nunca sabe = we never know (anyone, me too).
• No pronoun for the unknown "they". Eles dizem que vai chover sounds like specific people. Say Dizem que vai chover.
• Singular without se needs a subject. Bateu na porta sounds unfinished; an unknown knocker is Bateram na porta.
• Zero subject is spoken. Aqui vende chip? is perfect at a newsstand, but write Vendem-se chips on the sign.

If you speak Spanish

Most of this transfers: se venden casas → vendem-se casas, robaron mi bici → roubaram minha bicicleta. Watch three things. First, the position: Spanish always puts se first, Portuguese writing never starts with it (Vende-se, Trata-se de). Second, se busca / se necesitan in ads become Procura-se and Precisa-se de, with de and a singular verb. Third, generic uno doesn’t exist: cuando uno está cansado → quando a gente está cansado or quando você está cansado. And for se dice que, Brazilians say Dizem que; Diz-se que is formal writing.