Prevenir Conjugation in Spanish
The Spanish verb prevenir means to prevent, to warn, and it is a verb you will use again and again once you know it. Prevenir means to prevent or to warn, and it covers preventing accidents, warning someone about a danger and taking precautions. It follows the pattern of venir, with the present prevengo, the preterite previne and the future prevendré. Like every Spanish verb, prevenir changes its ending for each person and tense, and this page gives you the complete picture: every tense, every person, the gerund and the past participle, all from the verified conjugation tables. For example, in the present tense you say prevengo accidentes en el trabajo, and in the preterite you say previne enfermedades con la vacuna. Work through the tables below, read the notes for each tense, and then test yourself with the examples, the common mistakes and the quiz at the end of the page.
Quick facts
- Infinitive: prevenir
- English: to prevent, to warn
- Verb type: irregular verb, stem-changing (e → ie)
- Ending: -ir
- Gerund: previniendo
- Past participle: prevenido
- Auxiliary verb: haber (all perfect tenses are formed with haber + prevenido)
- Stem change: e → ie in the present, present subjunctive and imperative; nosotros and vosotros keep the original stem.
Pronunciation is not listed on this page: the verified tables do not include IPA for prevenir, so no pronunciation is given rather than an invented one. Prevenir follows venir: the present is prevengo, the preterite is previne, and the future is prevendré.
Full conjugation tables
Every form below comes from the verified conjugation tables for prevenir. The imperfect subjunctive is shown in its -ra forms; the -se forms use the same stem. For reflexive verbs, the pronoun column shows the reflexive pronoun that goes before each form.
Present indicative
| Person | Form |
|---|---|
| yo | prevengo |
| tú | previenes |
| él/ella/Ud. | previene |
| nosotros/as | prevenimos |
| vosotros/as | prevenís |
| ellos/ellas/Uds. | previenen |
Preterite
| Person | Form |
|---|---|
| yo | previne |
| tú | previniste |
| él/ella/Ud. | previno |
| nosotros/as | previnimos |
| vosotros/as | previnisteis |
| ellos/ellas/Uds. | previnieron |
Imperfect
| Person | Form |
|---|---|
| yo | prevenía |
| tú | prevenías |
| él/ella/Ud. | prevenía |
| nosotros/as | preveníamos |
| vosotros/as | preveníais |
| ellos/ellas/Uds. | prevenían |
Future
| Person | Form |
|---|---|
| yo | prevendré |
| tú | prevendrás |
| él/ella/Ud. | prevendrá |
| nosotros/as | prevendremos |
| vosotros/as | prevendréis |
| ellos/ellas/Uds. | prevendrán |
Conditional
| Person | Form |
|---|---|
| yo | prevendría |
| tú | prevendrías |
| él/ella/Ud. | prevendría |
| nosotros/as | prevendríamos |
| vosotros/as | prevendríais |
| ellos/ellas/Uds. | prevendrían |
Present perfect
| Person | Form |
|---|---|
| yo | he prevenido |
| tú | has prevenido |
| él/ella/Ud. | ha prevenido |
| nosotros/as | hemos prevenido |
| vosotros/as | habéis prevenido |
| ellos/ellas/Uds. | han prevenido |
Pluperfect
| Person | Form |
|---|---|
| yo | había prevenido |
| tú | habías prevenido |
| él/ella/Ud. | había prevenido |
| nosotros/as | habíamos prevenido |
| vosotros/as | habíais prevenido |
| ellos/ellas/Uds. | habían prevenido |
Future perfect
| Person | Form |
|---|---|
| yo | habré prevenido |
| tú | habrás prevenido |
| él/ella/Ud. | habrá prevenido |
| nosotros/as | habremos prevenido |
| vosotros/as | habréis prevenido |
| ellos/ellas/Uds. | habrán prevenido |
Conditional perfect
| Person | Form |
|---|---|
| yo | habría prevenido |
| tú | habrías prevenido |
| él/ella/Ud. | habría prevenido |
| nosotros/as | habríamos prevenido |
| vosotros/as | habríais prevenido |
| ellos/ellas/Uds. | habrían prevenido |
Present subjunctive
| Person | Form |
|---|---|
| yo | prevenga |
| tú | prevengas |
| él/ella/Ud. | prevenga |
| nosotros/as | prevengamos |
| vosotros/as | prevengáis |
| ellos/ellas/Uds. | prevengan |
Imperfect subjunctive (-ra)
| Person | Form |
|---|---|
| yo | previniera |
| tú | previnieras |
| él/ella/Ud. | previniera |
| nosotros/as | previniéramos |
| vosotros/as | previnierais |
| ellos/ellas/Uds. | previnieran |
Imperative (affirmative)
| Person | Form |
|---|---|
| tú | prevén |
| él/ella/Ud. | prevenga |
| nosotros/as | prevengamos |
| vosotros/as | prevenid |
| ellos/ellas/Uds. | prevengan |
Imperative (negative)
| Person | Form |
|---|---|
| tú | prevengas |
| él/ella/Ud. | prevenga |
| nosotros/as | prevengamos |
| vosotros/as | prevengáis |
| ellos/ellas/Uds. | prevengan |
Gerund and past participle
| Form | Spanish | Use |
|---|---|---|
| Gerund | previniendo | with estar for the progressive: estoy previniendo |
| Past participle | prevenido | with haber for the perfect tenses: he prevenido |
How to use each tense
Present indicative
Use the present for routines, general facts and what is happening right now. This tense is irregular for this verb: it follows the pattern of venir, with changes in the present, the preterite (the -vin- stem), the future and conditional, and the subjunctive. Learn the forms in the table rather than applying the regular endings. For prevenir, the present looks like this in a real sentence: Prevengo accidentes en el trabajo. Learn the present forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Preterite
Use the preterite for finished actions with a clear end, often with ayer, el año pasado or anoche. This tense is irregular for this verb: it follows the pattern of venir, with changes in the present, the preterite (the -vin- stem), the future and conditional, and the subjunctive. Learn the forms in the table rather than applying the regular endings. For prevenir, the preterite looks like this in a real sentence: Ayer, previne a los vecinos del corte de agua. Learn the preterite forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Imperfect
Use the imperfect for background, habits and actions in progress in the past, often with de niño, antes or mientras. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For prevenir, the imperfect looks like this in a real sentence: De niño, prevenía enfermedades con la vacuna. Learn the imperfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Future
Use the future for plans, predictions and promises, often with mañana, el año que viene or pronto. This tense is irregular for this verb: it follows the pattern of venir, with changes in the present, the preterite (the -vin- stem), the future and conditional, and the subjunctive. Learn the forms in the table rather than applying the regular endings. For prevenir, the future looks like this in a real sentence: Mañana, prevendré a su hijo del peligro. Learn the future forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Conditional
Use the conditional for polite requests, hypotheticals and what would happen, often with si clauses. This tense is irregular for this verb: it follows the pattern of venir, with changes in the present, the preterite (the -vin- stem), the future and conditional, and the subjunctive. Learn the forms in the table rather than applying the regular endings. For prevenir, the conditional looks like this in a real sentence: Prevendría accidentes en el trabajo si pudiera. Learn the conditional forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Present perfect
Use the present perfect for recent actions and experiences, often with hoy, esta semana or ya. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For prevenir, the present perfect looks like this in a real sentence: Hoy, he prevenido a los vecinos del corte de agua. Learn the present perfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Pluperfect
Use the pluperfect when one past action happened before another past action. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For prevenir, the pluperfect looks like this in a real sentence: Había prevenido enfermedades con la vacuna antes de salir. Learn the pluperfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Future perfect
Use the future perfect for something that will already be finished by a future time. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For prevenir, the future perfect looks like this in a real sentence: Para mañana, habré prevenido a su hijo del peligro. Learn the future perfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Conditional perfect
Use the conditional perfect for what would have happened under different conditions. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For prevenir, the conditional perfect looks like this in a real sentence: Habría prevenido accidentes en el trabajo con más tiempo. Learn the conditional perfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Present subjunctive
Use the present subjunctive after expressions of wish, doubt, emotion and hope, such as espero que or quiero que. This tense is irregular for this verb: it follows the pattern of venir, with changes in the present, the preterite (the -vin- stem), the future and conditional, and the subjunctive. Learn the forms in the table rather than applying the regular endings. For prevenir, the present subjunctive looks like this in a real sentence: Espero que él prevenga a los vecinos del corte de agua. Learn the present subjunctive forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Imperfect subjunctive (-ra)
Use the imperfect subjunctive after past wishes and in si clauses about the past, and note the -ra forms shown here; the -se forms use the same stem. This tense is irregular for this verb: it follows the pattern of venir, with changes in the present, the preterite (the -vin- stem), the future and conditional, and the subjunctive. Learn the forms in the table rather than applying the regular endings. For prevenir, the imperfect subjunctive looks like this in a real sentence: Si él previniera enfermedades con la vacuna, todo cambiaría. Learn the imperfect subjunctive forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Imperative (affirmative)
Use the affirmative imperative for direct commands, instructions and invitations. This tense is irregular for this verb: it follows the pattern of venir, with changes in the present, the preterite (the -vin- stem), the future and conditional, and the subjunctive. Learn the forms in the table rather than applying the regular endings. For prevenir, the affirmative imperative looks like this in a real sentence: ¡Prevén a su hijo del peligro! Learn the affirmative imperative forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Imperative (negative)
Use the negative imperative, always with no, to tell someone not to do something. This tense is irregular for this verb: it follows the pattern of venir, with changes in the present, the preterite (the -vin- stem), the future and conditional, and the subjunctive. Learn the forms in the table rather than applying the regular endings. For prevenir, the negative imperative looks like this in a real sentence: No prevengas accidentes en el trabajo. Learn the negative imperative forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Example sentences
Ten natural sentences with prevenir, covering different tenses and persons. Each one uses a form from the tables above.
- Prevengo accidentes en el trabajo. — I prevent accidents at work.
- Previene a los vecinos del corte de agua. — He/she prevents the neighbours about the water cut.
- Ayer, previne enfermedades con la vacuna. — Yesterday, I prevented illnesses with the vaccine.
- Antes, nosotros preveníamos a su hijo del peligro. — Before, we used to prevent his son about the danger.
- Mañana, tú prevendrás accidentes en el trabajo. — Tomorrow, you will prevent accidents at work.
- Yo prevendría a los vecinos del corte de agua si tuviera más tiempo. — I would prevent the neighbours about the water cut if I had more time.
- Él ha prevenido enfermedades con la vacuna. — He has prevented illnesses with the vaccine.
- Espero que él prevenga a su hijo del peligro. — I hope he prevents his son about the danger.
- Yo ya había prevenido accidentes en el trabajo antes de salir. — I had already prevented accidents at work before leaving.
- Ellos prevenían a los vecinos del corte de agua cuando eran jóvenes. — They used to prevent the neighbours about the water cut when they were young.
Common mistakes
- Wrong: Yo previene accidentes en el trabajo. — Right: Yo prevengo accidentes en el trabajo. — The person matters: previene is the él/ella/Ud. form, while the yo form is prevengo. Using the third-person form with yo is one of the most common beginner errors.
- Wrong: Yo preveno a los vecinos del corte de agua. — Right: Yo prevengo a los vecinos del corte de agua. — Prevenir is a stem-changing verb (e → ie), so the stem changes in the present singular and third-person plural. The nosotros form keeps the original stem.
- Wrong: Treating prevenir and evitar as identical in every context. — Right: Prevenir means to prevent, to warn, while evitar means to avoid. — They overlap, but each has uses the other does not: prevenir fits sentences such as Prevengo accidentes en el trabajo, while evitar belongs in a different sentence. Check the meaning you want before choosing.
- Wrong: Yo soy prevenido a los vecinos del corte de agua. — Right: Yo he prevenido a los vecinos del corte de agua. — Spanish perfect tenses use haber, not ser: he prevenido, has prevenido, ha prevenido. Ser plus the participle makes a passive, not a perfect tense.
- Wrong: De niño, yo previne enfermedades con la vacuna todos los días. — Right: De niño, yo prevenía enfermedades con la vacuna todos los días. — For a repeated habit in the past, use the imperfect (prevenía), not the preterite. The preterite (previne) is for one finished action.
Quiz: test yourself
Ten questions on prevenir. Choose the right form, then check the answer key below.
Complete the sentence: Yo ___ accidentes en el trabajo. (present tense) A. prevengo B. previenes C. previene D. prevenimos
Complete the sentence: Ayer, él ___ a los vecinos del corte de agua. (preterite) A. previne B. previniste C. previnieron D. previno
Complete the sentence: Antes, nosotros ___ enfermedades con la vacuna. (imperfect) A. prevenías B. prevenían C. preveníamos D. prevenía
Complete the sentence: Mañana, tú ___ a su hijo del peligro. (future) A. prevendremos B. prevendrás C. prevendré D. prevendrá
Complete the sentence: Yo ___ accidentes en el trabajo si pudiera. (conditional) A. prevendría B. prevendrías C. prevendrían D. prevengo
Complete the sentence: Espero que él ___ a los vecinos del corte de agua. (present subjunctive) A. prevengas B. prevengamos C. prevengo D. prevenga
Complete the sentence: Si yo ___ enfermedades con la vacuna, todo cambiaría. (imperfect subjunctive, -ra form) A. previniéramos B. prevengo C. previniera D. previnieras
Complete the sentence: Nosotros ___ a su hijo del peligro. (present perfect) A. han prevenido B. hemos prevenido C. he prevenido D. has prevenido
Complete the command: ¡___ accidentes en el trabajo! (affirmative imperative, tú) A. prevén B. prevenga C. prevengamos D. prevenid
Which is the gerund of prevenir, used with estar for the progressive? A. prevenido B. prevengo C. previne D. previniendo
Answer key
- prevengo — The first-person present of prevenir is prevengo. The other options are the tú, él/ella and nosotros forms.
- previno — The third-person preterite of prevenir is previno, the form for a single finished action in the past.
- preveníamos — The nosotros imperfect of prevenir is preveníamos, used here for a repeated past habit.
- prevendrás — The second-person future of prevenir is prevendrás.
- prevendría — The first-person conditional of prevenir is prevendría, the form for what would happen.
- prevenga — After espero que, the subjunctive is required: the third-person present subjunctive of prevenir is prevenga.
- previniera — The first-person imperfect subjunctive (-ra) of prevenir is previniera.
- hemos prevenido — The nosotros present perfect of prevenir is hemos prevenido: hemos + prevenido.
- prevén — The affirmative tú imperative of prevenir is prevén.
- previniendo — The gerund of prevenir is previniendo: estoy previniendo. The participle prevenido is used with haber instead.
Frequently asked questions
What does prevenir mean in English?
Prevenir means to prevent, to warn. It is used in everyday situations such as Prevengo accidentes en el trabajo. The exact English wording depends on the context, but the core meaning stays the same across the tenses.
Is prevenir regular or irregular?
Prevenir is a stem-changing verb (e → ie), so it is not fully regular: the stem changes in the present, the present subjunctive and the imperative, while nosotros and vosotros keep the original stem. The preterite and the imperfect are regular. Check the tables above for the exact forms in each tense.
What is the difference between prevenir and evitar?
Prevenir means to prevent, to warn, while evitar means to avoid. They are easy to confuse because they appear in similar situations, but they are not interchangeable: use prevenir when you mean to prevent, to warn, as in Prevengo accidentes en el trabajo, and use evitar for to avoid. When in doubt, check the object of the sentence — it usually shows which verb fits.
How do I say “I prevent” in the past?
It depends on the kind of past. For one finished action, use the preterite: yo previne a los vecinos del corte de agua. For a repeated habit or background in the past, use the imperfect: yo prevenía enfermedades con la vacuna. For something that has just happened, use the present perfect: yo he prevenido a los vecinos del corte de agua.
How do I practise prevenir?
Start with the present tense table, then drill the preterite and the imperfect, since those two past tenses cause the most mistakes. Try the prevenir examples and quiz page for more sentences, and use the Spanish Verb Quiz to test the forms under pressure.
Related links
- Prevenir in the preterite tense — the full preterite-tense table for prevenir.
- Prevenir examples and quiz — more example sentences and practice for prevenir.
- Spanish verbs — the Spanish hub, with every verb and tense guide.
- Complete list of Spanish irregular verbs — where this verb's pattern is listed.
- Convenir conjugation — another -ir verb to compare with prevenir.
- Intervenir conjugation — another -ir verb to compare with prevenir.
- Provenir conjugation — another -ir verb to compare with prevenir.
- Spanish Verb Conjugator — conjugate any Spanish verb in every tense.
- Spanish Verb Quiz — test yourself on real conjugated forms.