The passive voice

Voice is the grammatical category that expresses the relationship between a verb and its subject. In the active voice the subject performs the action; in the passive voice it undergoes it. Turning an active clause into a passive one adds no new information — it reorganises it, promoting what was the direct object to subject and pushing the agent into the background, when it does not delete it altogether. Portuguese has two distinct passive constructions: the analytic (or participial) and the pronominal (with se).

The analytic passive

The analytic passive is formed with the auxiliary verb ser (“to be”) + the past participle of the main verb. The auxiliary carries the inflection of tense, mood and person; the participle behaves like an adjective and agrees in gender and number with the subject.

Any tense and mood is available, because all the inflection falls on ser: é lido (“is read”), era lido, foi lido, será lido, seria lido, que seja lido, ter sido lido. Only directly transitive verbs allow this passive, since it depends on there being a direct object to promote to subject.

The passive agent

The doer of the action is called the passive agent and is introduced by the preposition por (“by”), often contracted: pelo, pela, pelos, pelas. The preposition de appears in some cases of state or feeling — amado de todos (“loved by all”), conhecido de muitos (“known to many”) — but is now largely literary.

The passive’s most useful trait is precisely that it can omit the agent when it is unknown, obvious or irrelevant. This is what makes it so frequent in journalistic, scientific and administrative prose.

The pronominal passive

The second passive is built with the pronoun se, the so-called passive se (partícula apassivadora), alongside a verb in the third person. In meaning it is equivalent to an analytic passive with an unspecified agent.

The decisive point — and the most common error — is agreement: because the noun is the true subject, the verb is singular or plural to match it. Vende-se uma casa (“a house is for sale”), but vendem-se casas (“houses are for sale”); aluga-se um quarto, but alugam-se quartos. Shop signs reading «vendem-se carros» are therefore grammatically correct.

The placement of se

Being an unstressed (clitic) pronoun, the passive se follows the general rules of pronoun placement in European Portuguese: enclisis by default (Resolveu-se o problema, “the problem was solved”), but proclisis when an attracting word is present — negation, an adverb, a subordinating conjunction, a relative pronoun (Não se resolveu o problema; quando se resolveram os problemas).

Passive of action and passive of state

The true passive, with ser, must be kept apart from the construction with estar + participle, which expresses not an action but the resulting state of one. The first describes an event; the second, a situation.

Construction	Example	Value
ser + participle	A porta foi fechada (pelo guarda).	action / passive of action
estar + participle	A porta está fechada.	resulting state / passive of state

A porta foi fechada reports the act of closing; a porta está fechada (“the door is closed”) describes its current condition, without saying by whom or when. That is why the passive of state seldom takes an agent: ?a porta está fechada pelo guarda sounds odd.

Double participles

Several verbs have two participles — a regular one, preferred with ter and haver (“to have”), and an irregular (short) one, preferred with ser and estar. In the passive voice the irregular form is, as a rule, the one chosen.

Verb	Regular (ter/haver)	Irregular (ser/estar)
aceitar (accept)	tinha aceitado	foi aceite
pagar (pay)	tinha pagado	está pago
entregar (deliver)	tinha entregado	foi entregue
imprimir (print)	tinha imprimido	foi impresso

When to use each

The two passives are not freely interchangeable. The analytic one prevails when the agent is expressed or easily recovered and when the tense must be marked precisely. The pronominal one is lighter and more impersonal, at home in instructions, notices and generalisations — Fala-se português (“Portuguese spoken”), Proíbe-se fumar (“No smoking”), Servem-se refeições (“Meals served”) — and it is exactly there that agreement deserves the closest attention.