Breakdown of A água do lago foi limpa por voluntários na semana passada.
ser
to be
a água
the water
de
of
em
in
limpar
to clean
por
by
a semana
the week
passado
last
o lago
the lake
o voluntário
the volunteer
Questions & Answers about A água do lago foi limpa por voluntários na semana passada.
Why is there a before água?
In Portuguese, most nouns are used with a definite article. água is feminine singular, so it takes a (the feminine singular article). Saying a água means “the water.” Omitting the article is rare here and sounds informal or poetic.
What does do in do lago stand for?
do is the contraction of de + o meaning “of the.” Since lago is masculine singular, de + o contracts to do, so do lago literally means “of the lake.”
How do we form the passive voice in Portuguese, as in foi limpa?
You combine the appropriate tense of ser with the past participle of the main verb. Here, foi is the third-person singular preterite of ser, and limpa is the past participle of limpar. Together, foi limpa means “was cleaned.”
Why is the past participle limpa feminine?
In a true passive construction with ser, the past participle must agree in gender and number with the subject. The subject here is a água (feminine singular), so the participle is limpa, not limpo.
Why do we use por voluntários instead of pelos voluntários?
por voluntários (no article) means “by volunteers” in a general sense. If you say pelos voluntários (por + os), it becomes “by the volunteers,” referring to a specific group you’ve already mentioned or both speaker and listener know about.
What is the difference between foi limpa and está limpa?
foi limpa uses ser in the preterite plus participle, a true passive voice indicating that an action happened (“was cleaned”). está limpa uses estar plus participle to describe a resulting state (“is clean”) rather than the action of cleaning.
Why is na semana passada used for “last week”?
na is the contraction of em + a (“in the”). semana passada literally means “week past.” So na semana passada = “in the week past,” i.e. “last week.” You could also say na última semana, but na semana passada is more common for “last week.”
Could we rewrite this sentence in active voice?
Yes. The active version is “Voluntários limparam a água do lago na semana passada.” Here voluntários is the subject doing the action, limparam is the third-person plural preterite of limpar, and a água do lago is the direct object.
In voluntários, can we use voluntárias?
Yes—if the group of volunteers is entirely female, you would use voluntárias (feminine plural). Portuguese nouns and adjectives must agree in gender and number with the people or things they describe.
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