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Identical Twins: IR and SER
One of the strangest things to happen to Spanish verbs is to take on the exact same irregular preterite form, and this happens with the very common verbs ir and ser. Who knows why these two verbs evolved over the course of time to have the same preterite past tense form, but they do make life complicated if you’re unfamiliar with them.
Study the charts below:
Going or Being? The Problem with FUI

Now that you’ve memorized the verb forms for ir and ser, you may be wondering how in the world you will ever know whether a sentence with the word fui means “I went” or “I was.”
Quite simply, by context! You’ll have to figure out which verb is meant by the rest of the words in the sentence. It’s not as hard as it sounds. See if you can guess the meaning of the verbs in the examples below:
1. Nosotros fuimos a la piscina la semana pasada.
2. Ayer fue un día muy aburrido.
3. Tú fuiste la persona que me robó.
Answers:
1. We went to the pool last week.
ir
2. Yesterday was a very boring day.
ser
3. You were the person who robbed me.
ser
Want to learn more about Spanish Tenses? Take a look at these lessons:
- The common Spanish preterite
- The Spanish imperfect tense refers to a past action. Confused? Learn more here.
- Unfortunately, you are going to find many irregular verbs in the Spanish preterite tense. This tense lesson unravels all the mystery!
See you soon! ¡Hasta pronto!
Mauricio Evlampieff: Rocket Spanish