intervenir Preterite Conjugation
intervenir — to intervene
Intervenir is highly irregular in the preterite, following the 'u-stem' pattern (intervin-).
intervenir Preterite Forms
When to Use the Preterite
Use the preterite to describe a specific moment when someone stepped in or a surgery was performed. It marks a completed action in the past.
Notes on intervenir in the Preterite
This verb follows the pattern of 'venir'. The stem changes to 'intervin-' and it uses special endings: -e, -iste, -o, -imos, -isteis, -ieron (no accents).
Example Sentences
El cirujano intervino al paciente de urgencia.
The surgeon operated on the patient urgently.
él/ella/usted
Yo intervine en la discusión para calmar los ánimos.
I intervened in the argument to calm things down.
yo
Ellos intervinieron el teléfono del sospechoso.
They tapped the suspect's phone.
ellos/ellas/ustedes
Common Mistakes
Mistake: Writing 'intervinio' or 'intervenió'.
Correct: intervino
Why: Irregular preterites like this one do not have an accent on the 'o' in the third person.
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Related Tenses
Present
yo: intervengo
Intervenir is irregular in the present, featuring a 'g' in the 'yo' form and an 'ie' stem change in others.
Imperfect
yo: intervenía
The imperfect of intervenir is regular: intervenía, intervenías, intervenía...
Future
yo: intervendré
The future tense of intervenir uses the irregular stem 'intervendr-'.
Conditional
yo: intervendría
The conditional uses the irregular stem 'intervendr-' followed by regular -ía endings.
Present Subjunctive
yo: intervenga
Intervenir is irregular in the present subjunctive, using the stem 'interveng-' for all persons.
Imperfect Subjunctive
yo: interviniera
The imperfect subjunctive uses the irregular stem 'intervinier-' for all forms.
Affirmative Imperative
yo: intervén
The imperative uses the short form 'intervén' for the informal 'tú' command.
Negative Imperative
yo: no intervengas
The negative imperative always uses the present subjunctive forms with 'no'.