al + infinitive
on doing / when doing
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on doing / when doing
Al + infinitive introduces when something happens: Al llegar, llamó. The infinitive often shares the main subject, but can have an explicit one: Al llegar Juan, salimos.
Examples in context
Read the examples and compare their English meanings.
Immediate Sequence
Use to mean 'upon doing' something.
Al abrir la puerta, vio un gato.
Upon opening the door, she saw a cat.
Cause and Effect
Shows the action triggered the result.
Al correr tan rápido, se cayó.
By running so fast, he fell down.
Common mix-ups
After al, use the infinitive abrir. This construction can have its own explicit subject, as in al llegar Juan.
When I opened the door, I saw a cat.
Try a reply
Say or write your answer in Spanish before opening the example.
Upon leaving, I closed the door. Use al.
Show one possible answer
Al salir, cerré la puerta.
Other wording can work too. Compare the verb form, agreement, and word order with the lesson. Then try a sentence about your own day.
Keep practicing
Related grammar
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