Imperfect or preterite? In the Spanish indicative mood, we can find two ways to describe an action in the past. Generally, the preterite is used for completed actions (actions that have definite start and ending points.) These can be actions that can be viewed as single events, actions that were part of a chain of events, actions that were repeated a very specific number of times, or actions that specifically state the beginning and end of an action. For example "Estudié en el extranjero - I studied abroad (not anymore). There are many helpful words and phrases that indicate specific time frames, therefore signaling that the preterite should be used (yesterday, last night, the other day, last week, days ago...to name a few).