Preterite vs imperfect
Spanish has two simple past tenses, and they don’t differ in time. They differ in how you look at the action. The preterite shows an event from outside, as a finished dot on the timeline. The imperfect puts you inside the scene, where the action is still going on.
Flip the verbs, change the story
Tap any highlighted verb to switch it between imperfect and preterite. The timeline shows how each choice changes the picture: a bar is ongoing background, a dot is a finished event.
Era un sábado de agosto y mucho calor. Mis amigos y yo en la playa. Mientras yo un libro, de repente a llover. Todos al coche. Ese día a Lucía, que la hermana de un amigo.
leía means I was reading (in progress). This is the most natural choice in this story.
Use the preterite for…
- Completed events with a start or end: Ayer fui al cine.
- A sequence of actions: Llegó, se sentó y pidió un café.
- The event that interrupts an ongoing scene: …cuando sonó el teléfono.
- Actions with a defined duration: Viví en Lima tres años.
Use the imperfect for…
- Background and description: La casa era grande y hacía sol.
- Habits (“used to”, “would”): Cada verano íbamos a la playa.
- Actions in progress (“was doing”): Leía cuando llegaste.
- Time, age, feelings: Eran las ocho. Tenía sueño.
Verbs that change meaning
| Verb | Preterite | Imperfect |
|---|---|---|
| conocer | conocí I met | conocía I knew |
| saber | supe I found out | sabía I knew |
| querer | quise I tried · no quise I refused | quería I wanted |
| poder | pude I managed · no pude I failed | podía I could, was able |
| tener | tuve I got, received | tenía I had |
Endings side by side
| Preterite -ar | Preterite -er/-ir | Imperfect -ar | Imperfect -er/-ir | |
|---|---|---|---|---|
| yo | -é | -í | -aba | -ía |
| tú | -aste | -iste | -abas | -ías |
| él/ella | -ó | -ió | -aba | -ía |
| nosotros | -amos | -imos | -ábamos | -íamos |
| vosotros | -asteis | -isteis | -abais | -íais |
| ellos | -aron | -ieron | -aban | -ían |
Only three verbs are irregular in the imperfect: ser (era), ir (iba) and ver (veía). The preterite has many more; see the Spanish past tense guide.
Frequently asked questions
What is the difference between the preterite and the imperfect?
The preterite presents a past action as a completed event with a clear boundary (Ayer comí paella). The imperfect presents it as ongoing background, a habit or a description with no focus on its end (De niño comía paella todos los domingos).
Which tense do I use for age, time and weather in the past?
Normally the imperfect, because they are background descriptions: Eran las tres. Tenía diez años. Hacía frío. Use the preterite only if you present them as a bounded event: Hizo frío toda la semana.
Are there words that signal the preterite or imperfect?
Trigger words help but are not rules. Ayer, anoche, una vez, de repente and el año pasado often go with the preterite; siempre, todos los días, a menudo, mientras and de niño often go with the imperfect.
Do some verbs change meaning between the two tenses?
Yes. Conocí means “I met”, conocía “I knew”; supe “I found out”, sabía “I knew”; quise “I tried”, no quise “I refused”; pude “I managed to”, podía “I was able to”.