Quick answer
Llovía y no había nadie. Entonces perdí el autobús.
It was raining and there was nobody around. Then I missed the bus. The imperfecto paints the scene; the indefinido moves the story forward.
The words of this lesson
One holiday, two tenses
Here is the story you are going to build: el año pasado fui a Cádiz con dos amigos. Era agosto y hacía mucho calor. El primer día perdimos el autobús, así que fuimos a pie hasta la playa. Read it again and watch which verbs do what.
The indefinido — fui, perdimos, fuimos — is the chain of events. Each one happened, finished, and pushed the story one step on. The imperfecto — era, hacía — is the backdrop: the month, the weather, the mood. It has no end point, because it is not an event at all.
Which one moves the story
Ask one question of every verb: does this advance the plot, or does it describe the stage the plot happens on? Advancing takes the indefinido, describing takes the imperfecto. Llovía (background) y entonces llegó el taxi (event). No había nadie en la calle (background) cuando salimos del hotel (event).
Two words point each way. De repente, entonces, al final and a stated number of times pull the indefinido: fuimos tres veces. Mientras, siempre, todos los días and normalmente pull the imperfecto: todos los días desayunábamos en el mismo bar.
The shape of a told story
Native stories almost always open in the imperfecto and then switch. Set the scene first — era domingo, estábamos cansados, no teníamos plan — and only then drop in the event: de repente Ana propuso ir a la playa. Ending the same way is common too: al final volvimos a las tres de la mañana.
English gives you almost no help here, because "it was raining" and "it rained" both come out as one past for most learners. The tense you pick is a choice about what kind of thing you are saying, not about how long ago it was.
Where you are matters
Latin America uses <span class="es-inline">¿qué hicieron?</span> where Spain says <span class="es-inline">¿qué hicisteis?</span> Spain also reaches for the perfect for today’s events (<span class="es-inline">hoy he perdido el autobús</span>), while most of Latin America keeps the indefinido: <span class="es-inline">hoy perdí el autobús</span>.
Memory trick
Imperfecto paints the stage, indefinido moves the story. Ask which one each verb is doing.
A short dialogue
Typical mistakes
Ayer llovía todo el día y fuimos a casa.
Ayer llovió todo el día.
With a closed block of time seen as finished, the event tense is right. Llovía would leave the day open as background.
Era agosto y fue mucho calor.
Era agosto y hacía mucho calor.
Weather as background takes the imperfecto, and hot weather uses hacer, not ser.
Mientras comimos, llegó mi hermano.
Mientras comíamos, llegó mi hermano.
Mientras describes an action in progress, so it takes the imperfecto; the interrupting event keeps the indefinido.
Practice
Practise these a story in the past
0/8 matched — tap a Spanish word, then its translation
Check yourself
Which version tells the story the way a native speaker would?