Preterite vs imperfect: How to use each one?

Publicado el 24 de marzo de 2025 por Cecilia N.

Background vs. foreground

Watch the following video and read the description.

La sala de interrogatorios estaba en penumbra. Las paredes grises acentuaban la frialdad del ambiente. La mesa y las sillas aguardaban en su lugar, dispuestas para el encuentro. De pronto, la puerta se abrió y dos detectives entraron con paso firme. Uno de ellos tomó asiento mientras el otro cerraba la puerta tras de sí. Ambos se situaron frente a la mesa, preparados para iniciar el interrogatorio.

The interrogation room was dimly lit. The gray walls added to the cold, sterile atmosphere. The table and chairs sat in place, waiting for the encounter. Suddenly, the door swung open, and two detectives walked in with a firm stride. One of them took a seat while the other shut the door behind him. Both positioned themselves in front of the table, ready to begin the interrogation.

Let’s answer the following questions:

1. Which verbs describe the environment or context in the scene?
Estaba, acentuaban, aguardaban (all in imperfect)

2. Which verbs indicate concrete actions that changed the scene?
Se abrió, entraron, tomó, cerró, se situaron (all in preterite)

Just as dim lighting, static objects, and general atmosphere create context in a video, we use the imperfect in narration to describe the background setting where the story unfolds:how the room looked, what was there, and what was happening at that moment.

• “La sala de interrogatorios estaba en penumbra.”
• “Las paredes grises acentuaban la frialdad del ambiente.”
• “La mesa y las sillas aguardaban en su lugar…” 

When a notable change occurs in the scene (like when the door opens and the detectives enter), these specific actions break the static background and move the story forward. We use the preterite to express these decisive moments.

• “…dos detectives entraron con paso firme.”
• “Uno de ellos tomó asiento…”
• “Ambos se situaron frente a la mesa…” 

Ejercicio #1

Other uses of the preterite and imperfect

The activity above gives us a general idea of how the preterite and imperfect work, especially in storytelling. Now let’s look at specific uses of both tenses.

Ejercicio #2

Contrasting both tenses

Here are comparisons between the preterite and imperfect with verbs that express similar ideas but have different meanings depending on which tense is used.

Preterite
Fui al cine ayer.
I went to the movies yesterday.

Imperfect
Iba al cine cuando llegaste.
I was going to the movies when you arrived.

Preterite
Se enfermó de repente.
He got sick suddenly.

Imperfect
Se enfermaba de pequeño.
He used to get sick when he was a child.

Preterite (Meeting for the first time)
Conocí a tu hermana ayer.
I met your sister yesterday.

Imperfect (Knowing from before)
El taxista conocía bien la ciudad.
The taxi driver knew the city well.

Preterite (Finding out)
Supe la noticia esta mañana.
I found out the news this morning.

Imperfect (Having knowledge)
Sabía la noticia pero no dije nada.
I knew about the news, but I didn’t say anything.

Preterite (Achievement)
Al final pude resolver el problema.
In the end, I managed to solve the problem.

Imperfect (Ability)
Podía levantar 100 kilos.
I could/was able to lift 100 kilos.

Preterite
Fui al gimnasio ayer.
I went to the gym yesterday.

Imperfect
Siempre iba al gimnasio los lunes.
I always used to go to the gym on Mondays.

Preterite
El niño se puso triste cuando se le perdió el juguete.
The child got sad when he lost his toy.

Imperfect

El niño se ponía triste cuando su papá se iba a trabajar.
The child would get sad when his dad left for work.

Preterite
La economía colapsó en 2008.
The economy collapsed in 2008.

Imperfect
La economía colapsaba y nadie hacía nada.
The economy was collapsing and no one was doing anything.

Preterite
Dormí ocho horas y luego me levanté.
I slept for eight hours and then got up.

Imperfect
Dormía mientras mi esposo cuidaba a la bebé.
I was sleeping while my husband took care of the baby.

Preterite
Amó el regalo que le dieron.
He loved the gift they gave him.

Imperfect
Amaba a su familia.
He loved his family.

Ejercicio #3

Preterite conjugations

To conjugate verbs in the preterite, follow these steps:

Step 3

Add the corresponding endings.

yo → –é → hablé
yo → –í → comí
yo → -í → viví

Regular verbs

Regular verbs have no changes in their stem or endings.

The following table shows regular verb endings; note that -er and -ir share the same endings.

Irregular verbs in the preterite

Irregular preterite verbs have alterations in their stems or endings:

Tener → Irregular stem: tuv- Yo tuve, tú tuviste, él tuvo, nosotros tuvimos…

Hacer → Irregular stem: hic- (hiz- in 3rd person singular) Yo hice, tú hiciste, él hizo, nosotros hicimos…

Estar (instead of -é, -aste, -ó like “hablar”)
Yo estuve, tú estuviste, él estuvo…

Venir (instead of -í, -iste, -ió like “vivir”)
Yo vine, tú viniste, él vino…

“Comer” (regular): yo comí, él/ella/usted comió
“Tener” (irregular): yo tuve, él/ella/usted tuvo

“Vivir” (regular): yo viví, él/ella/usted vivió
“Decir” (irregular): yo dije, él/ella/usted dijo

“Comer” (regular): yo comí, él/ella/usted comió
“Tener” (irregular): yo tuve, él/ella/usted tuvo

“Vivir” (regular): yo viví, él/ella/usted vivió
“Decir” (irregular): yo dije, él/ella/usted dijo

-e, -iste, -o, -imos, -isteis, -ieron/-eron

Estar → estuv: estuve, estuviste, estuvo, estuvimos, estuvisteis, estuvieron
Traer → traj: traje, trajiste, trajo, trajimos, trajisteis, trajeron

Classification of irregular preterite verbs

Irregular verbs can be classified into several groups:

c → qu: buscar (busqué)
g → gu: pagar (pagué)
z → c: empezar (empecé)
gu → gü: averiguar (averigüé)

ser/ir: share the same form (fui, fuiste, fue, fuimos, fuisteis, fueron)

dar: di, diste, dio, dimos, disteis, dieron (keeps stem but with special endings)

ver: vi, viste, vio, vimos, visteis, vieron

Important irregular preterite verbs

Time expressions used with preterite

Anoche ella dijo “oh cariño, me siento tan deprimida…”
Last night she said “oh baby I feel so down…”

Ayer me encontré con un amigo en la cafetería del barrio.
Yesterday I met a friend at the local café.

Anteayer fui a correr por el parque antes de que amaneciera.
The day before yesterday I went for a run in the park before sunrise.

El otro día vimos una película buenísima.
The other day we watched a great movie.

El lunes pasado tuve una reunión en la oficina.
Last Monday I had a meeting at the office.

El mes pasado celebramos el cumpleaños de mi tío.
Last month we celebrated my uncle’s birthday.

Hace tres días, mi hermana se mudó a su nuevo apartamento.
Three days ago, my sister moved to her new apartment.

La semana pasada fuimos a un asado en casa de un vecino.
Last week we went to a barbecue at a neighbor’s house.

Compramos una casa con piscina por cinco mil dólares en el 79.
We bought a house with a pool for five thousand dollars in ’79.

Una vez, durante un viaje por carretera, me perdí y descubrí un pequeño pueblo encantador.
Once, during a road trip, I got lost and discovered a charming little town.

Estaba hablando con mi vecino cuando de repente su perro me atacó.
I was talking to my neighbor when suddenly his dog attacked me.

…en ese momento supe que tenía que trabajar hasta tarde.
…at that moment I knew that I had to work until late.

…y entonces todos vivieron felices para siempre.
…and then they all lived happily ever after.

Conjugations in the imperfect tense

To conjugate verbs in the imperfect, remove the -ar, -er, -ir ending and add the appropriate endings.

Hablar → habl → hablaba (yo)
Comer → com → comía (yo)
Vivir → viv → vivía (yo)

Endings for the imperfect tense

Note that -er and -ir verbs share the same endings.

Irregular verbs in the imperfect tense

Only three verbs are irregular in the imperfect: ser, ir, and ver.

Time expressions used with imperfect

Mis abuelos iban a misa todos los domingos.
My grandparents used to go to church every Sunday.

Antes me gustaba la remolacha. Ahora la detesto.
I used to like beets, now I hate them.

Normalmente me levantaba temprano para aprovechar el día.
Normally, I would wake up early to make the most of the day.

Mi abuela me preparaba a menudo un desayuno saludable.
My grandmother often prepared a healthy breakfast for me.

Frecuentemente invitábamos a los vecinos a la casa.
We would often invite the neighbors over to our house.

Mientras mi hermana estudiaba, yo ayudaba en la cocina.
While my sister studied, I would help in the kitchen.

Generalmente, hacía senderismo los fines de semana.
I usually went hiking on the weekends.

En aquella época, vivíamos en un pequeño pueblo.
At the time, we lived in a small town.

Todos los días jugábamos en el patio hasta que oscurecía.
Every day, we played in the yard until it got dark.

Durante las vacaciones de verano, viajábamos a la playa.
During the summer vacations, we would to travel to the beach.

Cuando era niño, me encantaba leer cuentos antes de dormir.
When I was a child, I loved reading stories before bed.