17.2 exercise: inflection of the past participle in the passive voice
Some languages, for instance Portuguese, Spanish and german distinguish between a passive voice that describes a process and a passive voice, that describes the result of this process and others, like French, Italian and English don't make this distinction. However as far as English is concerned the difference is easy to understand. The continuous form in English always describes an ongoing action and if we form the passive voice with the continuous form we describe a process.
the result of a process: The cake was eaten (and therefore we got nothing).
the process: The cake was being eaten (when we arrived).
In practice there can be an enormous difference. If you go to a birthday party and the cake was eaten or has been eaten you have a result. There is no cake for you. If you go to a party and the cake was being eaten or has been being eaten there is already something left and you have a good chance to get some. (English native speakers would avoid this construction, although it is grammatically correct. However it serves to understand the difference between a passive voice that describes a process and a passive voice that describes the result of a process.)
The distinction made in English with a continuous form is done in Portuguese with the verb ser. The English continuous form is formed in Portuguese and Spanish with ser, the result of a process is formed with the verb estar. It is to assume that English native speakers would avoid construction of the type "The car was being repaired when we arrived" and that they would say "They have been repairing the car when we arrived". However it is crucial to see that the meaning of 1) "Os carros são reparados" and 2) "Os carros estão reparados" is completely different. In case 1) they were repairing the cars and in case 2) the cars are already respaired. 1) describes a process, 2) describes the result of a process.
Pay attention to the fact that the past participle has to agree in number and gender with the subject of the sentence.
passive voice describing a process (actually on should translate with a continuous form)
subject
auxiliary verb ser
past participle
tense
Os carros
são
reparados.
presente
The cars
are
repaired
O carro
é
reparado.
The car
is
repaired
Os carros
foram
reparados.
pretérito perfeito simples
The cars
were
repaired.
O carro
foi
reparado.
The car
was
repaired
Os carros
tinham sido
reparados.
pretérito mais-que-perfeito composto
The cars
had been
repaired.
Os carros
serão
reparados.
futuro I
The cars
will be
respaired
passive voice describing the result of a process
Os carros
estão
reparados.
presente
The cars
are
repaired.
O carro
está
reparado.
The car
is
repaired.
O carro
esteve
reparado.
pretérito perfeito simples
The car
was
repaired.
O carro
tinha estado
reparado.
pretérito mais-que-perfeito composto
The car
had been
repaired.
O carro
estará
reparado.
futuro I
The car
will be
repaired.
The fact that the past participle has to agree in number and gender with the subject is not a special rule. The past participle is actually kind of an adjective, whether used as an adjectival way (the books read) or whether used in predicative way (the book is read) it has to agree just like any adjective in number and gender to the noun it refers to.
O bolo é feito.
They make a cake.
Os bolos são feitos.
The cakes were made.
O bolo doce esta sobre a mesa.
The sweet cake is on the table.
Os bolos doces estão sobre a mesa.
The sweet cakes are on the table.
A carta é escrita.
The letter is being written.
As cartas são escritas.
They were writing the letters.
A carta escrita esta sobre a mesa.
The written letter is on the table.
As cartas escritas estão sobre a mesa.
The written letters are on the table.
Any noun, adjective, participle, pronoun in any adjective or predicative use has to agree in gender and number with the noun it refers to.
A casa é branca.
The house is white.
A casa é destruída.
The house is destroyed.
A casa é minha.
It's my house.
Branca, destruida and minha are used in a predicative way, are connected to the noun through to be and have therefore to agree in gender and number with noun they refer to. The past participle isn't an exception. We would have a specific rule if that were not the case.
Choose in the following sentences the auxiliary verb that corresponds to the verbal tense and the corresponding past participle. In opposite to other roman languages and English the present perfect does NOT correspond to the Portuguese pretérito perfeito composto, see pretérito perfeito composto. Therefore the correct answer could be deduced from the context, but not from the English translation. To simplify things we indicate the time to be used.