Pretérito e Imperfecto

The Pretérito is for completed actions. Think of it as a box with a lid. You know exactly when it started and ended. The Imperfecto is for ongoing or repeated actions. It has no clear beginning or end in the moment. It is the "was" or "used to" of Spanish. Imagine you are watching a play. The stage lights, the background, and the costumes are the Imperfecto. The actors walking onto the stage and dropping a tray? That is the Pretérito. One provides the background music. The other provides the beat. If you say Ayer comí, you finished eating. If you say Comía, you are describing the habit of eating. It is like choosing between a photo and a video.

1. 1For the Pretérito, change -ar endings to -é, -aste, -ó, -amos, -asteis, -aron.
2. 2For -er and -ir verbs, use -í, -iste, -ió, -imos, -isteis, -ieron.
3. 3The Imperfecto is often easier to remember for you.
4. 4-ar verbs take -aba, -abas, -aba, -ábamos, -abais, -aban.
5. 5-er and -ir verbs take -ía, -ías, -ía, -íamos, -íais, -ían.
6. 6Watch out for the three rebels in the Imperfecto: ser, ir, and ver.
7. 7The Pretérito has many more irregulars like ir, ser, and hacer.
8. 8Practice these patterns until they feel like muscle memory.

Use the Pretérito for specific events at specific times. "Yesterday, I bought a taco." Ayer, compré un taco. Use it for a sequence of events. "I woke up, showered, and left." Use the Imperfecto for habits and recurring actions. "I used to eat tacos every Tuesday." Comía tacos todos los martes. Use it for descriptions of people, places, and weather. "The sun was shining." Hacía sol. Use it for age and time in the past. "When I was ten..." Cuando tenía diez años... Use it for mental states and feelings. "I was happy." Estaba feliz. It feels like you are painting a picture for your listener.

Do not use the Pretérito for background states that lasted. If you were feeling sad for a whole week, use Imperfecto. Do not use the Imperfecto for sudden interruptions. If a dog barked once, that is Pretérito. Avoid using Imperfecto for lists of completed actions. If you graduated, got a job, and moved, those are all Pretérito. It is like a movie edit. Don't use a slow-motion shot for a quick punch. Also, don't use Pretérito for the "was -ing" construction. That is a job for the Imperfecto.

Many people use fue when they should use era. If you describe a person's personality, use era. "He was nice." Él era simpático. If you describe a completed event, use fue. "The party was fun." La fiesta fue divertida. Another mistake is forgetting trigger words. Ayer (yesterday) usually triggers the Pretérito. Siempre (always) usually triggers the Imperfecto. Don't let the irregulars scare you too much. Even if you mess up a conjugation, people will still understand. Just don't say you "used to die" when you mean you "died" once! That would be a very long and confusing story for your friends.

In English, we often use "used to" or "was -ing". This is your best friend for the Imperfecto. "I was walking" is Caminaba. For the Pretérito, think of the simple past "-ed". "I walked" is Caminé. However, Spanish is stricter about the "feeling" of the time. English is a bit lazier with these distinctions. In Spanish, the tense choice tells the listener if the action is over. It creates a sense of closure or continuation. Think of Pretérito as a dot on a timeline. Think of Imperfecto as a wavy line with no end.