Introduction
Understanding unfinished-action expressions with por plus the infinitive helps learners describe actions that were about to happen, intended, interrupted, or remained incomplete. This compact structure is common in spoken and written Spanish and is essential for clear, natural expression.
- What is the por + infinitive construction?
- Common meanings and nuances
- How to form and use it step by step
- Contrast with similar constructions
- Examples in different tenses and persons
- Negative and reflexive forms
- Usage notes and regional variation
- Common mistakes and how to avoid them
- Cultural and conversational tips
- Quick reference summary
- Conclusion
What is the por + infinitive construction?
The por + infinitive construction uses the preposition por followed by an infinitive verb to indicate an action that was going to occur but did not reach completion, or an action that was intended. It often translates to expressions in English like about to, supposed to, meant to, or was going to.
Basic structure
Form: por + infinitive
Examples:
por salir
por llamar
por terminar
Common meanings and nuances
There are several related meanings depending on context and tense. Below are the main uses with explanations and examples.
1. About to / on the verge of
Use por + infinitive to express that someone was about to do something when another event happened. The action is imminent but interrupted or prevented.
Example:
Estaba por salir cuando sonó el teléfono.
He was about to leave when the phone rang.
Example:
Ella estaba por contestar el correo cuando se fue la luz.
She was about to answer the email when the power went out.
2. Supposed to / intended to
When describing obligations that were expected or plans that did not occur, por + infinitive can convey supposed or intended actions.
Example:
Yo estaba por llamar a Juan, pero olvidé.
I was supposed to call Juan, but I forgot.
Example:
Estábamos por comer cuando llegaron los invitados.
We were about to eat when the guests arrived.
3. Just about to happen in narrative
In storytelling, the construction helps create suspense by signaling an action that almost occurred. It pairs well with past progressive tenses but can appear with simple past too.
Example:
La puerta se abrió cuando el ladrón estaba por entrar.
The door opened when the thief was about to enter.
Note that in formal or carefully edited text, other constructions might be preferred, but por + infinitive remains common in spoken narrative.
How to form and use it step by step
Follow these steps to use por + infinitive correctly.
Step 1: Choose the appropriate verb tense
You typically pair por + infinitive with a form of estar or a past/future tense that places the context in time. Common combinations:
– Imperfect progressive: estaba por + infinitive (was about to)
– Simple past: estuvo por + infinitive (rare; used regionally or in specific contexts)
– Present: estoy por + infinitive (I am about to)
Step 2: Add the infinitive
Use the base form of the verb after por. No conjugation of the following verb is needed because the infinitive carries the idea of the action itself.
Examples:
Estoy por salir.
Estaba por terminar mi tarea.
Step 3: Add context to show interruption or intention
The sentence often makes clear why the action did not complete or what interrupted it. Common connectors: cuando, pero, cuando de repente, sin embargo.
Examples:
Estaba por subir las escaleras cuando empezó a llover.
Iba a entrar a la reunión; estaba por entrar, pero me llamaron por teléfono.
Contrast with similar constructions
Several Spanish structures express near-completion or intention. Understanding differences helps choose the right expression.
Por + infinitive vs. Ir a + infinitive
Ir a + infinitive indicates a planned future action or a near future. It does not inherently imply interruption.
Estoy por salir. = I am about to leave (imminent, possibly interrupted).
Voy a salir. = I am going to leave (plan or near future).
Por + infinitive vs. Estar a punto de + infinitive
Estar a punto de + infinitive is very similar in meaning to por + infinitive and often interchangeable. Estar a punto de sounds slightly more explicit about being at the exact point of action, while por + infinitive can be a bit more colloquial.
Estaba por salir. = She was about to leave.
Estaba a punto de salir. = She was just about to leave.
Por + infinitive vs. Tener que + infinitive
Tener que + infinitive expresses obligation rather than imminence or interrupted intent. Do not confuse supposed to with must.
Estaba por llamar. = I was about to call / I was supposed to call.
Tenía que llamar. = I had to call (obligation).
Examples in different tenses and persons
Seeing the construction with different subjects and tenses clarifies usage.
Present:
Estoy por empezar la reunión.
I am about to start the meeting.
Imperfect:
Estabas por salir cuando te llamé.
You were about to leave when I called you.
Preterite (rare/colloquial contexts):
Estuvo por decir la verdad, pero no lo hizo.
He was about to tell the truth, but he did not.
Conditional/future nuance:
Estaría por ir si tuviera tiempo.
I would be about to go if I had time.
Negative and reflexive forms
Negation is straightforward: place no before the conjugated verb. Reflexive verbs keep the reflexive pronoun in front of the infinitive or attached to it depending on the structure.
Negative:
No estaba por ir al concierto.
I was not about to go to the concert.
Reflexive:
Estaba por dormirme cuando sonó la alarma.
I was about to fall asleep when the alarm rang.
Usage notes and regional variation
While por + infinitive is widely understood across the Spanish-speaking world, frequency and preference vary by region. Speakers in Spain and many Latin American countries also commonly use estar a punto de or estar para in related contexts.
Colloquial variation:
In casual conversation, you may hear simpler forms like iba a + infinitive to express similar ideas, especially for intended actions that simply did not happen. Iba a + infinitive tends to emphasize intent or plan rather than immediate interruption.
Formal writing:
In formal texts, authors sometimes prefer estar a punto de or other more explicit constructions to avoid ambiguity. For spoken Spanish and everyday writing, por + infinitive is perfectly natural.
Common mistakes and how to avoid them
Beginners make a few predictable errors when learning this construction. Here are pitfalls and corrections.
Mistake: Using por with a conjugated verb.
Incorrect: Por fui salir.
Correct: Estaba por salir or Iba por salir is not correct; use Iba a salir or Estaba por salir.
Mistake: Confusing obligation with imminence.
Incorrect: Estaba por terminar la tarea. (when meaning I had to finish it)
Correct: Tenía que terminar la tarea if you mean obligation.
Mistake: Leaving out context that shows interruption or intention.
While not always necessary, adding a temporal or causal clause helps clarify that the action did not complete.
Cultural and conversational tips
Using por + infinitive makes your Spanish sound natural and fluent in everyday conversation. Native speakers use it to signal interruptions, near misses, and intentions in storytelling and casual chat.
Tip: Pair it with time markers and sudden-event verbs.
Words like cuando, de repente, and verbs like sonar, entrar, llegar emphasize the interruption and make the narrative vivid.
Tip: Use it to soften excuses or explain missed plans.
If you missed an appointment, saying Estaba por salir pero se retrasó el transporte sounds natural and less blunt than a flat apology.
Quick reference summary
– Form: por + infinitive.
– Main meanings: about to, supposed to, intended to, on the verge of.
– Common with estar: estaba por + infinitive for past situations.
– Alternative: estar a punto de, ir a for planned future, tener que for obligation.
Conclusion
Mastering the por + infinitive construction expands your ability to describe imminent actions, interrupted plans, and intentions in natural Spanish. Practice noticing it in conversations and media, and try using it to explain near-misses and plans that changed. With a few examples and context clues, this compact structure becomes an indispensable part of your conversational toolkit.
