Preterite vs Imperfect
The two simple Spanish past tenses split English's single past tense between them. The decision isn't subjective - the rules are clear once you have them.
The decision rules
Preterite for:
- Completed actions in a closed time frame (ayer, la semana pasada, en 2020)
- Actions with a specified duration that has ended (trabajé dos horas, viví allí cinco años)
- A single event, or a sequence of events forming a narrative
- The interrupting event in a "while X was happening, Y happened" structure
Imperfect for:
- Habitual or repeated actions (every day, every Sunday, used to)
- Ongoing past actions ("was X-ing")
- Background description (the scene, the weather, ages, time of day)
- Mental and emotional states (knew, wanted, thought)
- The interrupted action in a "while X was happening, Y happened" structure
Time markers as triggers
| Triggers preterite | Triggers imperfect |
|---|---|
| ayer | siempre |
| anoche | normalmente |
| la semana pasada | todos los días |
| el año pasado | mientras |
| en 2020 | cuando era niño |
| hace dos años | de niño / joven |
| una vez | a menudo |
| el otro día | en aquella época |
If you see one of these in the sentence, it tells you which tense to reach for. When neither appears, you decide by context.
Side-by-side examples
| Spanish (preterite) | Spanish (imperfect) | Notes |
|---|---|---|
| Ayer comí paella. | Comía paella todos los domingos. | One occasion vs habit |
| Viví en Madrid dos años. | Vivía en Madrid cuando era estudiante. | Bounded duration vs background |
| Fui al cine anoche. | Iba al cine cada viernes. | One event vs habit |
| Ana llegó a las ocho. | Cuando yo llegué, Ana hablaba por teléfono. | Bounded events vs the ongoing one |
| Hizo mucho calor el sábado. | Hacía mucho calor. | Closed past vs setting the scene |
| Tuve un coche rojo (a specific one I bought and sold). | Tenía un coche rojo (the one I owned at the time). | Bounded ownership vs ongoing state |
Interrupted action: the most common composite
A characteristic Spanish past-tense structure: imperfect for the ongoing action, preterite for the event that interrupts it.
- Cuando llegué, María dormía. (When I arrived, Maria was sleeping.)
- Mientras hablaba con mi madre, sonó el teléfono. (While I was talking with my mother, the phone rang.)
- Estaba duchándome cuando se cortó el agua. (I was showering when the water cut off.)
The imperfect sets the stage, the preterite delivers the event. This is the bedrock structure of Spanish narration.
Verbs that change meaning
Five common verbs shift their core meaning between the two tenses. Worth memorising as a set.
| Verb | Imperfect (state) | Preterite (bounded event) |
|---|---|---|
| conocer | conocía = knew (a person, a place) | conocí = met (for the first time) |
| saber | sabía = knew (a fact) | supe = found out, learnt |
| querer | quería = wanted | quise = tried, made the attempt |
| no querer | no quería = didn't want | no quise = refused, decided not to |
| poder | podía = could, was able | pude = managed to, succeeded |
| no poder | no podía = couldn't | no pude = failed to, didn't manage |
| tener | tenía = had (state) | tuve = got, received (event) |
Examples:
- Conocí a mi mujer en 2010. (I met my wife in 2010 - the event.)
- Conocía a María antes de la universidad. (I knew Maria before university - the ongoing state.)
- Supe la verdad ayer. (I found out the truth yesterday - moment of finding out.)
- Sabía la verdad desde hace meses. (I had known the truth for months - state.)
- Quise llamarte pero no pude. (I tried to call you but I failed to - both bounded events.)
- Quería llamarte pero no podía. (I wanted to call you but I wasn't able to - ongoing state.)
These distinctions don't translate cleanly into English. Spanish is doing semantic work in the choice of tense.
Worked examples
- El año pasado fui a México y visité Ciudad de México. (Last year I went to Mexico and visited Mexico City.) - bounded preterite chain
- Cuando era niño, mi familia y yo íbamos a la playa cada verano. (When I was a child, my family and I used to go to the beach every summer.) - habitual imperfect
- María estaba cocinando cuando llegué a casa. (Maria was cooking when I got home.) - imperfect + preterite
- El restaurante estaba lleno y hacía mucho calor. (The restaurant was full and it was very hot.) - background imperfect
- Empecé a estudiar a las ocho y terminé a las once. (I started studying at eight and finished at eleven.) - bounded preterite
Common mistakes English speakers make
Defaulting to the preterite for everything because it feels closer to English simple past. The imperfect covers habitual and ongoing past, and missing it is the surest marker of an English-speaking learner. Conversely, using the imperfect for a bounded event because the duration is long: viví en Madrid cinco años is preterite (bounded duration, ended), not imperfect. And missing the meaning-shifting verbs - conocí a María and conocía a María are genuinely different sentences and shouldn't be used interchangeably.
See also
- The preterite page covers the full preterite conjugation including irregulars.
- The imperfect page covers the imperfect conjugation and its triggers.
- The intermediate Spanish grammar page covers the full past-tense system including past perfect.