Imponer in the Preterite Tense
Imponer means “to impose”, and this page covers exactly one thing: imponer in the preterite tense. The preterite is the tense Spanish speakers reach for when they talk about what is finished and done. On this page you will find the full preterite table for imponer, how the tense is formed for this verb, the situations where it is used, how it differs from the imperfect, worked examples, the mistakes learners make most often, an eight-question quiz with explained answers, and answers to the questions students ask about imponer in the preterite. For example: “Ayer, yo impuse una multa al conductor.” — Yesterday, I imposed a fine on the driver. Everything on this page uses the forms of imponer exactly as they are conjugated in the preterite, so you can trust every form you see here.
Imponer in the Preterite Tense — full table
| Person | Form |
|---|---|
| yo | impuse |
| tú | impusiste |
| él/ella/Ud. | impuso |
| nosotros/as | impusimos |
| vosotros/as | impusisteis |
| ellos/ellas/Uds. | impusieron |
Gerund: imponiendo · Past participle: impuesto
The gerund is imponiendo, which you use with estar to say what is happening right now: “Estoy imponiendo” means the action of imponer is in progress at this very moment. The past participle is impuesto, which you use with haber in the perfect tenses: “he impuesto” is the present perfect, used for a completed action. Keep both forms in mind as you read the examples below, because the preterite is only one part of how imponer is used.
How the preterite of imponer is formed
Imponer does not use one regular stem in this tense, so the forms below do not follow the simple stem + endings pattern. This tense is irregular for this verb: it follows the pattern of poner, with a -g- in the present (as in compongo), a -s- stem in the preterite (as in compuse), and an irregular participle (as in compuesto). Learn the forms in the table rather than guessing them from the infinitive. Learn the six forms as a set: yo impuse, tú impusiste, él/ella/Ud. impuso, nosotros/as impusimos, vosotros/as impusisteis, ellos/ellas/Uds. impusieron.
The irregularity of imponer is in its past participle, impuesto, not in the preterite, so the table above is the whole story for this tense. Remember the participle for the perfect tenses: he impuesto, has impuesto, ha impuesto.
When to use the preterite of imponer
The preterite is not a single-purpose tense. Below are the five situations where you will use imponer in the preterite most often. Each one comes with a real example, so read the rule, then say the example out loud.
1. One finished action
The preterite reports a single action that started and finished in the past. The action is done, counted once, and the story moves on. Example: “Ayer, yo impuse una multa al conductor.” — Yesterday, I imposed a fine on the driver.
2. A sequence of events
In a story, each preterite form is one step forward in time. When several things happened one after another, the preterite lists them in order. Example: “Nosotros impusimos reglas nuevas en el colegio.” — We imposed new rules in the school.
3. A specific time marker
Time words such as ayer, anoche, el año pasado and la semana pasada point to the preterite. They name a finished moment, and the verb must match. Example: “Él impuso su opinión en la reunión ayer.” — He imposed his opinion in the meeting yesterday.
4. A sudden change or interruption
The preterite describes sudden changes and interruptions: something happened, and the situation was different afterwards. Example: “Ellos impusieron un castigo al alumno de repente.” — They imposed a punishment on the pupil suddenly.
5. A completed time frame
When an action took place inside a period of time that is now over, the preterite is the right tense, because the period itself is finished. Example: “Tú impusiste una multa al conductor la semana pasada.” — You imposed a fine on the driver last week.
Preterite Tense vs Imperfect: how to choose
The closest tense to the preterite is the imperfect, and choosing between them is one of the hardest decisions in Spanish. The rule is simple: the preterite reports one finished action, while the imperfect describes background, habits in the past, or an action that was in progress when something else happened. The three pairs below use the same verb, so the only thing that changes is whether the action is finished and counted, or ongoing and descriptive. Time words help: ayer and de repente point to the preterite, while mientras and todos los días in the past point to the imperfect.
Preterite Tense: “Ayer, yo impuse una multa al conductor.” — Yesterday, I imposed a fine on the driver.
Imperfect: “Yo imponía una multa al conductor cada día.” — I used to impose a fine on the driver every day.
The preterite sentence reports one finished action; the imperfect sentence describes a habit in the past. Ayer points to the preterite, cada día in the past points to the imperfect.
Preterite Tense: “Anoche, él impuso reglas nuevas en el colegio.” — Last night, he imposed new rules in the school.
Imperfect: “Él imponía reglas nuevas en el colegio todos los días.” — He used to impose new rules in the school every day.
Anoche names one finished night, so the preterite is right; todos los días in the past describes a routine, so the imperfect is right.
Preterite Tense: “Nosotros impusimos su opinión en la reunión ayer.” — We imposed his opinion in the meeting yesterday.
Imperfect: “Nosotros imponíamos su opinión en la reunión cuando éramos jóvenes.” — We used to impose his opinion in the meeting when we were young.
The preterite sentence counts one finished action; the imperfect sentence describes how things used to be. That difference — finished event versus background — is the whole decision.
Example sentences: imponer in the preterite
Read these eight sentences out loud. They cover all six persons, so by the end you will have seen every form in the table used in a real sentence. Pay attention to the words around the verb — the time expressions, the objects, the other verbs — because those are what make each sentence sound natural.
“Impuse una multa al conductor.” — I imposed a fine on the driver.
“Impusiste reglas nuevas en el colegio.” — You imposed new rules in the school.
“Impuso su opinión en la reunión.” — He/she imposed his opinion in the meeting.
“Impusimos un castigo al alumno.” — We imposed a punishment on the pupil.
“Impusisteis una multa al conductor.” — You imposed a fine on the driver.
“Impusieron reglas nuevas en el colegio.” — They imposed new rules in the school.
“Impuse su opinión en la reunión.” — I imposed his opinion in the meeting.
“Impuso un castigo al alumno.” — He/she imposed a punishment on the pupil.
Common mistakes with imponer in the preterite
These are the errors learners actually make with this verb in this tense. Each one shows the wrong version, the right version, and why the correction matters.
Wrong: “Ellos impuso una multa al conductor.” Right: “Ellos impusieron una multa al conductor.” Why: Ellos needs the ellos form impusieron. The singular impuso belongs with él, ella or a singular noun.
Wrong: “Ayer yo imponí reglas nuevas en el colegio.” Right: “Ayer yo impuse reglas nuevas en el colegio.” Why: Imponer has an irregular preterite: the correct first-person form is impuse, not the regular imponí.
Wrong: “Nosotros impusiste su opinión en la reunión.” Right: “Nosotros impusimos su opinión en la reunión.” Why: Nosotros needs impusimos. The tú form impusiste belongs with tú.
Wrong: “Ellos impuse un castigo al alumno.” Right: “Ellos impusieron un castigo al alumno.” Why: The verb must agree with its subject. Ellos needs the ellos form impusieron, not the yo form impuse.
Quiz: imponer in the preterite
Choose the correct answer for each question, then check the answer key. Every answer is explained, so a wrong answer still teaches you something.
1. Complete the sentence: “Yo ______ una multa al conductor.” (A fine on the driver.)
- (a) impuse
- (b) impusiste
- (c) impuso
Answer: impuse — The yo form of imponer in the preterite is impuse. The other options are the forms for different persons, so they do not agree with the subject.
2. Complete the sentence: “¿Tú ______ reglas nuevas en el colegio?” (New rules in the school.)
- (a) impuse
- (b) impuso
- (c) impusiste
Answer: impusiste — The tú form of imponer in the preterite is impusiste. The other options are the forms for different persons, so they do not agree with the subject.
3. Complete the sentence: “Él ______ su opinión en la reunión.” (His opinion in the meeting.)
- (a) impusiste
- (b) impuso
- (c) impuse
Answer: impuso — The él/ella/Ud. form of imponer in the preterite is impuso. The other options are the forms for different persons, so they do not agree with the subject.
4. Complete the sentence: “Nosotros ______ un castigo al alumno.” (A punishment on the pupil.)
- (a) impusimos
- (b) impuse
- (c) impusiste
Answer: impusimos — The nosotros/as form of imponer in the preterite is impusimos. The other options are the forms for different persons, so they do not agree with the subject.
5. What is the vosotros/as form of imponer in the preterite?
- (a) impuse
- (b) impusiste
- (c) impusisteis
Answer: impusisteis — From the table above: vosotros/as takes impusisteis. Say it with the example sentence “Vosotros impusisteis una multa al conductor.” to fix it in your memory.
6. Complete the sentence: “Ellos ______ reglas nuevas en el colegio.” (New rules in the school.)
- (a) impusiste
- (b) impusieron
- (c) impuse
Answer: impusieron — The ellos/ellas/Uds. form of imponer in the preterite is impusieron. The other options are the forms for different persons, so they do not agree with the subject.
7. Which is the correct yo form of imponer in the preterite?
- (a) impuse
- (b) impusiste
- (c) impuso
Answer: impuse — The yo form is impuse. The other two options are the forms for other persons.
8. Which sentence describes one finished action in the past?
- (a) Yo imponía una multa al conductor cada día.
- (b) Mañana, yo impondré una multa al conductor.
- (c) Ayer, yo impuse una multa al conductor.
Answer: Ayer, yo impuse una multa al conductor. — “Ayer, yo impuse una multa al conductor.” reports a single completed event, so it takes the preterite. The second option describes background or a past habit, and the third looks to the future.
Frequently asked questions
Is imponer regular in the preterite?
No. Imponer has an irregular preterite: impuse, impusiste, impuso, impusimos, impusisteis, impusieron. Learn these forms as a set rather than deriving them from the infinitive.
What is the past participle of imponer?
The past participle is impuesto: 'He impuesto' means 'I have imposed'. It is used with haber in every perfect tense. The gerund is imponiendo.
When do I use the preterite instead of the imperfect for imponer?
Use the preterite for one finished action, as in Ayer, yo impuse una multa al conductor. Use the imperfect for a repeated habit or background, as in Yo imponía una multa al conductor cada día. The time words around the verb usually tell you which one fits.
How do I remember the preterite forms of imponer?
Say the six forms out loud in order, three times, with a real sentence for each one: yo impuse, tú impusiste, él/ella/Ud. impuso, nosotros/as impusimos, vosotros/as impusisteis, ellos/ellas/Uds. impusieron. Then write three of your own sentences with imponer in the preterite, using the examples on this page as models.
Related pages
- Full conjugation of imponer — every tense of imponer in one place.
- Imponer examples and quiz — more sentences with imponer and a ten-question quiz.
- Spanish preterite guide — how the preterite works for all Spanish verbs.
- Spanish verbs — the hub for every Spanish verb on VerbFlow.
- Preterite conjugator — conjugate any verb in the preterite instantly.
- Verb quiz — test yourself on imponer and other verbs.