Pretérito imperfeito

The short answer

The pretérito imperfeito (Portuguese imperfect) is the past seen from the inside: how things were, what used to happen and what was going on. Quando eu era criança, morava no interior — When I was a kid, I lived in the countryside. English often needs "used to", "would" or "was doing"; Portuguese uses one verb form for all of them.

How to form it

Drop -ar, -er or -ir and add the ending. -er and -ir verbs share one set.

• The eu and ele forms are the same: falava = I / you / he / she used to speak. Say the subject when it isn't clear: eu falava, ela falava.
• The nós form carries a written accent: falávamos, comíamos, abríamos.
• -ar verbs end in -ava, with a v.

Only four verbs are irregular:

Everything else is regular, even ir (ia, ia, íamos, iam), fazer (fazia) and dizer (dizia). In speech, estava is usually tava: Tava chovendo — It was raining.

When to use it

• Description and background: Era tarde e fazia frio.
• Habits ("used to", "would"): Todo domingo a gente almoçava na casa da minha avó.
• Age and stages of life: Quando eu tinha dez anos, jogava futebol na rua.
• Time and weather in the past: Eram oito horas e chovia muito.
• An action in progress: Eu tava saindo quando você ligou (estava + gerund).
• Typical signal words: antigamente (in the old days), sempre, todo dia, toda semana, naquela época (back then), quando eu era criança.

• Quando eu era criança, morava no interior de Goiás.When I was a kid, I lived in the countryside in Goiás.a stage of life
• Todo domingo a gente almoçava na casa da minha avó.Every Sunday we used to have lunch at my grandma’s.habit
• Era tarde, fazia frio e a rua estava vazia.It was late, it was cold and the street was empty.description
• Eu tava saindo quando você ligou.I was leaving when you called.in progress (tava = estava)

Contrasts and traps

• morava vs morei: Eu morava em Natal describes a period of your life from the inside; Morei dois anos em Natal sums it up as a finished block (perfeito). Choosing between the two is the next topic.
• ia + infinitive is "was going to": Eu ia sair, mas começou a chover. No a after ia.
• tinha also means "there was / there were" in speech: Tinha muita gente na festa (written: havia).
• era vs estava: the ser / estar split stays in the past. Ela era tímida (personality); ela estava cansada (state at that moment).
• No accent on -ia after a consonant: comia, dizia, abria. After a vowel it needs one: saía, caía.
• Politeness: Eu queria um café uses the imperfeito to soften a request, like English "I wanted to ask…".

If you speak Spanish

The imperfeito maps almost one-to-one onto the Spanish imperfecto: hablaba → falava, comía → comia, era → era, iba → ia. Spelling is where it goes wrong: -ava, not -aba; no accent on comia or tinha, but an accent on falávamos and comíamos. And tenía is tinha, venía is vinha, ponía is punha.