Compact Conditions with "De"
When reading formal warnings, safety procedures, or quick instructions, you will often see a very concise way to express "if" conditions in Spanish.
Instead of using si (if) with a conjugated verb, you can simply use the preposition de followed directly by an infinitive.
| If the protocol changes, notify the staff. | De cambiar el protocolo, avisad al personal. |
Notice how the subject of the condition (el protocolo) comes immediately after the infinitive (cambiar). This is the standard word order for this structure. The main instruction or result follows in the second half of the sentence, usually separated by a comma.
| If the machine fails, you must stay outside. | De fallar la máquina, debes permanecer fuera. |
| If the alarm sounds, the staff has to evacuate the building. | De sonar la alarma, el personal tiene que desalojar el edificio. |
If the infinitive verb requires an object or reflexive pronoun, attach it directly to the end of the infinitive to form a single word.
| If your head hurts, leave the mask here. | De dolerte la cabeza, deja la mascarilla aquí. |
| If the ship sinks, look for the life jacket. | De hundirse el barco, buscad el chaleco salvavidas. |
Finally, to express "if there is" or "if there are" using this structure, just use de haber.
| If there is an emergency, keep calm. | De haber una emergencia, mantened la calma. |
