al + Infinitive
Upon/When Doing
'Al + infinitive' means 'upon' or 'when' you do the action of the verb.
How It Works
The structure al + infinitive is a very common and useful way to connect two actions in time. It's formed from the contraction of the preposition a and the masculine singular definite article el, which combine to make al.
When you follow al with an infinitive verb (like hablar, comer, vivir), it means "upon" or "when" that action occurs. In a temporal reading it relates the main situation to the infinitive event, often as simultaneous or closely following it. There is no fixed maximum interval.
For example:
- Al llegar a casa, vi a mi perro. (Upon arriving home, I saw my dog.)
- Al abrir la puerta, sonó el teléfono. (When I opened the door, the phone rang.)
This is a more concise alternative to using a longer clause with cuando (when), like "Cuando llegué a casa...". It's very common in both spoken and written Spanish.
Subject And Other Readings
The infinitive need not have the same subject as the main verb: Al llegar María, todos saludaron (When María arrived, everyone said hello). A causal reading is possible: Al no tener dinero, decidió esperar (Since she had no money, she decided to wait). The surrounding sentence supplies time and interpretation.
Examples (4)
- Al salir de casa, vi a mi vecino.
Upon leaving the house, I saw my neighbor.
Word by Word: Upon to leave of house, I saw to my neighbor.
- Me puse nervioso al hablar en público.
I got nervous when speaking in public.
Word by Word: I became nervous upon to speak in public.
- Al entrar en la tienda, saludé al dependiente.
Upon entering the store, I greeted the clerk.
Word by Word: Upon to enter in the store, I greeted to the clerk.
- Ten cuidado al cruzar la calle.
Be careful when crossing the street.
Word by Word: Have care upon to cross the street.
Common Mistakes
Using 'cuando' with an infinitive instead of 'al'.
Cuando llegar a casa, te llamo.Al llegar a casa, te llamo.In the temporal construction intended here, use Al llegar a casa or Cuando llegue a casa. Bare Cuando llegar a casa does not form this clause. Interrogative cuándo can occur with an infinitive in a different structure, such as No sé cuándo salir (I do not know when to leave).
How It Connects
Learn This First
To understand 'al + infinitive', you need to know how the preposition 'a' contracts with the definite article 'el' to form 'al'. You also need to be familiar with the concept of an infinitive (the unconjugated form of a verb) which follows the contraction to express 'upon' or 'when' an action occurs.
- a/de/en/con/sinBasic Prepositions
The pattern 'al' is a contraction of the preposition 'a' and the definite article 'el'. Understanding the basic preposition 'a' is essential.
Foundations - el/la/los/lasDefinite Articles
The 'l' in 'al' comes from the masculine singular definite article 'el'. Knowledge of definite articles is required to understand the contraction.
Foundations - -o/-as/-a/-amos/-áis/-anPresent Tense -AR Verbs
To use 'al + infinitive', the learner must recognize the infinitive form of verbs (ending in -ar, -er, or -ir) as the base form before conjugation.
Level 1
Related Patterns
- después de + InfinitiveAfter Doing
Después de explicitly places the main event after the infinitive event. Al commonly links events temporally, but may also introduce a cause.
Level 1 - antes de + InfinitiveBefore Doing
Antes de places the main event before the infinitive event. Al has temporal and causal readings determined by context.
Level 1 - cuando + PreteriteWhen in Past Narration
For these temporal clauses, compare al + infinitive with cuando + conjugated verb. Interrogative cuándo is a different construction and can accompany an infinitive.
Level 2
Words in This Pattern
Practice al + Infinitive in Bubblegum
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