Breakdown of O computador foi inventado pelo cientista.
ser
to be
o computador
the computer
por
through / by / for / because of
o cientista
the scientist
Questions & Answers about O computador foi inventado pelo cientista.
Why do we use foi (from the verb ser) here instead of a past tense form of estar?
In Portuguese, the passive voice is formed using the verb ser, not estar. We use foi (the simple past of ser) because the act of inventing was a specific, completed event. The passive formula is always ser + past participle + por to show who did the action.
Would inventado change if the sentence was about a different object?
Yes! In the passive voice, the past participle (inventado) acts like an adjective and must match the subject in gender and number. Since o computador is masculine singular, it is inventado. If the subject was feminine, like a máquina (the machine), it would be a máquina foi inventada.
Why is the word pelo used before the scientist, rather than just por?
In passive sentences, the person doing the action is introduced by the preposition por (by). However, because we are talking about the specific scientist, por merges with the definite article o (the). Por + o creates the mandatory contraction pelo (by the).
Since cientista ends in an 'a', shouldn't it be pela cientista?