Pretérito perfeito — irregulares mais comuns
A handful of high-frequency verbs go their own way in the pretérito perfeito. The good news: there are only about a dozen, and they're the same in PT and BR (no accent split this time). The strangest pair: ser and ir share the same past — fui can mean both 'I was' and 'I went'. Context decides.
SER and IR — same forms, two meanings
fui, foste, foi, fomos, foram. Eu fui professor = I was a teacher (ser). Eu fui ao Porto = I went to Porto (ir). The clue is what comes after: a noun or adjective with no preposition → ser; a place with a, para, até → ir. Eu fui a Lisboa = I went to Lisbon. A festa foi boa = the party was good.
TER, ESTAR — the 'tive' family
ter: tive, tiveste, teve, tivemos, tiveram. Tive uma ideia = I had an idea. estar: estive, estiveste, esteve, estivemos, estiveram. Estive em casa = I was (located) at home. The two patterns rhyme — both keep -ive- in the stem. With estar, the perfeito means 'I was (at a time/place)' as a finished episode.
FAZER — fiz
fiz, fizeste, fez, fizemos, fizeram. Fazer = to do / to make (introduced here for the first time as a full vocab item, though you've seen faço in fazer anos, fazer compras type expressions). O que fizeste ontem? = What did you do yesterday? Fiz o jantar = I made dinner.
DIZER, VER, DAR
dizer (to say) — disse, disseste, disse, dissemos, disseram. The eu and 3rd-singular forms are spelled the same: eu disse / ela disse. ver (to see) — vi, viste, viu, vimos, viram. Tiny and tidy. dar (to give) — dei, deste, deu, demos, deram. Notice dar is the only verb here that takes the regular -ar -ei ending in the eu form.
Other useful irregulars
vir (to come) — vim, vieste, veio, viemos, vieram. poder (to be able) — pude, pudeste, pôde (with circumflex to distinguish from present pode), pudemos, puderam. querer (to want) — quis, quiseste, quis, quisemos, quiseram. saber (to know) — soube, soubeste, soube, soubemos, souberam (often means 'I found out'). trazer (to bring) — trouxe, trouxeste, trouxe, trouxemos, trouxeram.
Putting it together
Most of a Portuguese past-tense story runs on these dozen verbs plus the regular endings from lesson 16. Try a paragraph in your head: Ontem fui ao mercado, comprei comida, vi o meu primo, e disse-lhe olá. = Yesterday I went to the market, bought food, saw my cousin, and said hello to him. Mix the irregulars with regular -ar/-er/-ir freely.
