In short

The pretérito imperfeito is the past tense of describing rather than reporting. The pretérito perfeito simples of Lessons 20-21 tells you what happened once and finished (li o livro, “I read the book”; ela chegou, “she arrived”). The imperfeito instead paints the scene around such events: what things were like, what used to happen, and what was going on at the time (chovia, “it was raining”; tinha dez anos, “I was ten”; íamos sempre à praia, “we always used to go to the beach”). English spreads this job over three shapes - “was/were doing”, “used to do”, and habitual “would do” - and Portuguese folds all of them into this single tense. Better still, it is almost entirely regular: two ending patterns and just four irregular verbs.

The rule

What the imperfeito is for

Four jobs cover nearly everything you will need at this level.

1. Habits and repeated actions in the past - English “used to” or habitual “would”:
   • Quando era criança, brincava na rua. - When I was a child, I used to play in the street.
   • Ao domingo levantávamo-nos tarde. - On Sundays we would get up late.
2. Description and background - states, weather, the time, age, looks, feelings:
   • A casa era grande e tinha um jardim. - The house was big and had a garden.
   • Estava sol e não havia ninguém na praia. - It was sunny and there was nobody on the beach.
   • Eram três horas. - It was three o’clock.
3. An action in progress, either interrupted by a completed event or running beside another:
   • Eu jantava quando o telefone tocou. - I was having dinner when the phone rang.
   • Enquanto ela lia, eu cozinhava. - While she was reading, I was cooking.
4. Two softer uses you will hear constantly in Portugal:
   • Polite requests, where the imperfeito replaces a blunt present: Queria um café, se faz favor. - I’d like a coffee, please.
   • Informal hypotheticals, where speech uses it instead of the conditional: Eu, no teu lugar, não dizia nada. - In your place, I wouldn’t say anything.

Rule of thumb: if English can say “used to X” or “was Xing”, the imperfeito is almost always right; if it says a plain “X-ed” that reports one finished event, you want the perfeito simples instead.

Building it - regular verbs

Take the infinitive, drop -ar / -er / -ir, and add one of just two ending sets. Crucially, -er and -ir share the same endings (-ia), so there are really only two patterns to learn:

• -ar verbs (falar): stem fal- + -ava, -avas, -ava, -ávamos, -avam.
• -er and -ir verbs (comer, partir): stem + -ia, -ias, -ia, -íamos, -iam.

The nós form always carries a written accent on the stressed vowel - falávamos, comíamos, partíamos (recall the stress-and-accent rules from the reading & pronunciation guide). Forget it and you have misspelt the word.

The four irregular verbs

Only ser, ter, vir and pôr are irregular in the imperfeito - learn these four and you are done:

• ser -> era, eras, era, éramos, eram
• ter -> tinha, tinhas, tinha, tínhamos, tinham
• vir -> vinha, vinhas, vinha, vínhamos, vinham
• pôr -> punha, punhas, punha, púnhamos, punham

Note that ir is perfectly regular here (ia, ias, ia, íamos, iam), even though it was wildly irregular in the perfeito simples (fui, foi). Verbs built on the irregular four inherit their pattern: manter -> mantinha, conter -> continha, provir -> provinha, compor -> compunha, supor -> supunha.

Past progressive: estava a + infinitivo

To say “was doing” with extra stress on the action being under way, put estar into the imperfeito and keep the estar a + infinitivo frame from Lesson 9:

• Estava a ler quando chegaste. - I was (in the act of) reading when you arrived.
• O que estavas a fazer às oito? - What were you doing at eight?

The plain imperfeito (lia, fazia) already means “was reading / was doing”, so this longer form is optional emphasis, not a requirement.

Forms & patterns

Regular endings, side by side - notice the -er and -ir columns are identical:

The four irregular verbs in full:

Examples

Common mistakes

• A casa foi grande e teve um jardim -> A casa era grande e tinha um jardim - description of a past state takes the imperfeito, not the perfeito simples.
• Quando era criança, brinquei na rua (meaning a habit) -> brincava na rua - a repeated childhood habit is the imperfeito; brinquei would mean “I played once”.
• falavamos, comiamos, iamos -> falávamos, comíamos, íamos - the nós imperfeito always carries the written accent; dropping it is a spelling error.
• eu era built as seava/erava -> eu era - ser is irregular; there is no regular -ava form for it.
• eu tinha rendered as tia/tinhava -> eu tinha - ter is irregular too; the stem is tinh-, never ti- or tinhav-.
• punhava / ponhia -> punha - the imperfeito of pôr is punha, and compounds follow it (compunha, supunha).
• Quero um café as a polite order -> Queria um café - to sound courteous, swap the present for the imperfeito; the bare present can come across as abrupt.

Tips

• Test with English: if you can reword the sentence as “used to…” or “was …-ing”, the imperfeito fits; if it is a single finished event (”…-ed, and that was that”), use the perfeito simples of Lessons 20-21.
• You only ever memorise two regular patterns (-ava for -ar, -ia for both -er and -ir) and four irregular verbs (ser, ter, vir, pôr). Everything else is predictable.
• Keep the perfeito simples and the imperfeito as a team: the perfeito moves the story forward (a porta abriu-se), the imperfeito holds the backdrop still (estava escuro, ninguém falava). Lesson 23 drills the choice between them.
• For a softer, more Portuguese-sounding request, reach for queria, gostava de, podia, importava-se de rather than the present: Gostava de ver o menu., Podia abrir a janela?
• Say the nós forms out loud with the stress where the accent sits - fa-lá-va-mos, co-mí-a-mos - so the written accent becomes automatic.
• In Brazil: the past progressive is estar + gerund in the imperfeito - estava fazendo, estava lendo - exactly where European Portuguese uses estava a fazer, estava a ler.