Understanding when to use preterite vs imperfect is one of the biggest challenges for Spanish learners. These two past tenses describe different types of past actions, and choosing correctly is essential for clear communication.
The Core Difference: Completed vs Ongoing
The fundamental distinction is simple:
- Preterite: Completed actions with a clear beginning or end
- Imperfect: Ongoing actions without defined endpoints
Think of it this way: Preterite captures snapshots, while imperfect describes background scenes.
When to Use Preterite (Completed Actions)
Use preterite for these specific situations:
1. Single Completed Events
- Ayer comí a las dos. (Yesterday I ate at two.)
- Terminé el libro la semana pasada. (I finished the book last week.)
2. Actions with Specific Timeframes
- Viví en México por dos años. (I lived in Mexico for two years.)
- Estudié de ocho a diez. (I studied from eight to ten.)
3. Series of Completed Actions
- Me levanté, me vestí y salí. (I got up, got dressed, and left.)
- Llegué a casa, abrí la puerta y entré. (I arrived home, opened the door, and entered.)
4. Sudden Changes or Beginnings/Ends
- El teléfono sonó. (The telephone rang.)
- Empezó a llover. (It started to rain.)
When to Use Imperfect (Ongoing Actions)
Use imperfect for these background situations:
1. Habitual or Repeated Actions
- Cuando era niño, jugaba al fútbol. (When I was a child, I used to play soccer.)
- Siempre íbamos a la playa en verano. (We always went to the beach in summer.)
2. Ongoing Actions in Progress
- Mientras estudiaba, escuchaba música. (While I was studying, I was listening to music.)
- Ellos hablaban cuando llegué. (They were talking when I arrived.)
3. Descriptions in the Past
- Era una casa grande y blanca. (It was a big, white house.)
- Tenía los ojos azules. (He had blue eyes.)
4. Time, Age, and Weather in the Past
- Eran las tres de la tarde. (It was three in the afternoon.)
- Tenía veinte años. (I was twenty years old.)
- Hacía buen día. (It was a nice day.)
Key Trigger Words for Each Tense
Preterite Triggers:
- Ayer (yesterday)
- El año pasado (last year)
- De repente (suddenly)
- Una vez (one time)
- Anoche (last night)
Imperfect Triggers:
- Siempre (always)
- A menudo (often)
- Generalmente (generally)
- Mientras (while)
- Cuando era niño (when I was a child)
Real-Life Examples Showing Both Tenses
Example 1:
- Imperfect: Era las ocho de la noche. (It was eight at night.)
- Preterite: Empezó a llover. (It started to rain.)
Example 2:
- Imperfect: Estaba estudiando cuando… (I was studying when…)
- Preterite: …el teléfono sonó. (…the telephone rang.)
Example 3:
- Imperfect: Íbamos al cine todos los viernes. (We used to go to the movies every Friday.)
- Preterite: Pero la semana pasada fuimos el sábado. (But last week we went on Saturday.)
Common Verbs with Different Meanings
Some verbs change meaning depending on the tense:
Conocer
- Preterite: Conocí a María ayer. (I met María yesterday.)
- Imperfect: Conocía Madrid bien. (I knew Madrid well.)
Saber
- Preterite: Supe la verdad ayer. (I found out the truth yesterday.)
- Imperfect: Sabía la respuesta. (I knew the answer.)
Querer
- Preterite: Quise ayudarle. (I tried to help him.)
- Imperfect: Quería ayudarle. (I wanted to help him.)
Practice Tips for Mastery
- Learn the triggers – Memorize the key words that signal each tense
- Practice with stories – Write short paragraphs using both tenses
- Listen for context – Pay attention to how native speakers use these tenses
- Use our interactive exercises below to test your understanding
Quick Reference Chart
| Preterite | Imperfect |
|---|---|
| Completed actions | Ongoing actions |
| Specific times | Background descriptions |
| Single events | Habitual actions |
| Beginnings/ends | Time/age/weather |
Remember: If you’re describing what was happening (imperfect) when something occurred (preterite), you’ll often use both tenses in the same sentence.
→Ready to practice? Try our interactive exercises to master preterite vs imperfect in real contexts.
