Ella Verbsreforzar to strengthen Irregular Verb
At a glance: Reforzar (to strengthen) is a irregular verb in Spanish. In the present tense: refuerzo, refuerzas, refuerza, reforzamos, reforzáis, refuerzan. Yo, tú, ella/él and ellas/ellos change o to ue (refuerzo, refuerzas, refuerza, refuerzan); nosotros and vosotros are regular. It is also irregular in the preterite (reforcé) and present subjunctive (refuerce).

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The Indicative Present of reforzar is used to talk about situations, events or thoughts that are happening now or in the near future. It is also used to talk about facts and truths. For example, “refuerzo”, meaning “I strengthen”.
In Spanish, the Indicative Present is known as "El Presente".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | refuerzo | I strengthen |
| Tú | refuerzas | you strengthen |
| Ella / Él / Usted | refuerza | s/he strengthens |
| Nosotras / Nosotros | reforzamos | we strengthen |
| Vosotras / Vosotros | reforzáis | you (plural) strengthen |
| Ellas / Ellos / Ustedes | refuerzan | they strengthen |
How it’s built: Yo, tú, ella/él and ellas/ellos change o to ue (refuerzo, refuerzas, refuerza, refuerzan); nosotros and vosotros are regular.
Letters in red show where a form differs from the regular pattern.
The Indicative Preterite of reforzar is used to talk about actions completed in the past, at a specific point in time. For example, “reforcé”, meaning “I strengthened”.
In Spanish, the Indicative Preterite is known as "El Pretérito Indefinido".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | reforcé | I strengthened |
| Tú | reforzaste | you strengthened |
| Ella / Él / Usted | reforzó | s/he strengthened |
| Nosotras / Nosotros | reforzamos | we strengthened |
| Vosotras / Vosotros | reforzasteis | you (plural) strengthened |
| Ellas / Ellos / Ustedes | reforzaron | they strengthened |
How it’s built: Yo changes z to c (reforcé); the other forms are regular.
Letters in red show where a form differs from the regular pattern.
The Indicative Imperfect of reforzar is used to describe regular and repeated actions that happened in the past and descriptions of things you used to do. For example, “reforzaba”, meaning “I used to strengthen”.
In Spanish, the Indicative Imperfect is known as "El Pretérito Imperfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | reforzaba | I used to strengthen |
| Tú | reforzabas | you used to strengthen |
| Ella / Él / Usted | reforzaba | s/he used to strengthen |
| Nosotras / Nosotros | reforzábamos | we used to strengthen |
| Vosotras / Vosotros | reforzabais | you (plural) used to strengthen |
| Ellas / Ellos / Ustedes | reforzaban | they used to strengthen |
How it’s built: Regular: stem reforz- plus the -ar endings.
The Indicative Present Continuous of reforzar is used to talk about something that is happening continuously or right now. For example, “estoy reforzando”, meaning “I am strengthening”.
In Spanish, the Indicative Present Continuous is known as "El Presente Progresivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | estoy reforzando | I am strengthening |
| Tú | estás reforzando | you are strengthening |
| Ella / Él / Usted | está reforzando | s/he is strengthening |
| Nosotras / Nosotros | estamos reforzando | we are strengthening |
| Vosotras / Vosotros | estáis reforzando | you (plural) are strengthening |
| Ellas / Ellos / Ustedes | están reforzando | they are strengthening |
How it’s built: Estar in the present (estoy, estás, está, estamos, estáis, están) plus the gerund reforzando.
The Indicative Informal Future of reforzar is used to talk about something that will happen in the future, especially in the near future. For example, “voy a reforzar”, meaning “I am going to strengthen”.
In Spanish, the Indicative Informal Future is known as "El Futuro Próximo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | voy a reforzar | I am going to strengthen |
| Tú | vas a reforzar | you are going to strengthen |
| Ella / Él / Usted | va a reforzar | s/he is going to strengthen |
| Nosotras / Nosotros | vamos a reforzar | we are going to strengthen |
| Vosotras / Vosotros | vais a reforzar | you (plural) are going to strengthen |
| Ellas / Ellos / Ustedes | van a reforzar | they are going to strengthen |
How it’s built: Ir in the present (voy, vas, va, vamos, vais, van), then a, then the infinitive reforzar.
The Indicative Future of reforzar is used to talk about something that will happen in the future. For example, “reforzaré”, meaning “I will strengthen”.
In Spanish, the Indicative Future is known as "El Futuro Simple".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | reforzaré | I will strengthen |
| Tú | reforzarás | you will strengthen |
| Ella / Él / Usted | reforzará | s/he will strengthen |
| Nosotras / Nosotros | reforzaremos | we will strengthen |
| Vosotras / Vosotros | reforzaréis | you (plural) will strengthen |
| Ellas / Ellos / Ustedes | reforzarán | they will strengthen |
How it’s built: Regular: the infinitive reforzar plus the future endings.
The Indicative Conditional of reforzar is used to talk about something that may happen in the future, hypothesis and probabilities. For example, “reforzaría”, meaning “I would strengthen”.
In Spanish, the Indicative Conditional is known as "El Condicional Simple".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | reforzaría | I would strengthen |
| Tú | reforzarías | you would strengthen |
| Ella / Él / Usted | reforzaría | s/he would strengthen |
| Nosotras / Nosotros | reforzaríamos | we would strengthen |
| Vosotras / Vosotros | reforzaríais | you (plural) would strengthen |
| Ellas / Ellos / Ustedes | reforzarían | they would strengthen |
How it’s built: Regular: the infinitive reforzar plus the conditional endings.
The Indicative Present Perfect of reforzar is used to describe actions that started recently (in the past) and are still happening now or things that have been done recently. For example, “he reforzado”, meaning “I have strengthened”.
In Spanish, the Indicative Present Perfect is known as "El Pretérito Perfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | he reforzado | I have strengthened |
| Tú | has reforzado | you have strengthened |
| Ella / Él / Usted | ha reforzado | s/he has strengthened |
| Nosotras / Nosotros | hemos reforzado | we have strengthened |
| Vosotras / Vosotros | habéis reforzado | you (plural) have strengthened |
| Ellas / Ellos / Ustedes | han reforzado | they have strengthened |
How it’s built: Haber in the present (he, has, ha, hemos, habéis, han) plus the past participle reforzado.
The Indicative Past Perfect of reforzar is used to talk about actions that happened before another action in the past. For example, “había reforzado”, meaning “I had strengthened”.
In Spanish, the Indicative Past Perfect is known as "El Pretérito Pluscuamperfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | había reforzado | I had strengthened |
| Tú | habías reforzado | you had strengthened |
| Ella / Él / Usted | había reforzado | s/he had strengthened |
| Nosotras / Nosotros | habíamos reforzado | we had strengthened |
| Vosotras / Vosotros | habíais reforzado | you (plural) had strengthened |
| Ellas / Ellos / Ustedes | habían reforzado | they had strengthened |
How it’s built: Haber in the imperfect (había, habías, había, habíamos, habíais, habían) plus the past participle reforzado.
The Indicative Future Perfect of reforzar is used to talk about something that will have happened in the future after something else has already happened. For example, “habré reforzado”, meaning “I will have strengthened”.
In Spanish, the Indicative Future Perfect is known as "El Futuro Perfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | habré reforzado | I will have strengthened |
| Tú | habrás reforzado | you will have strengthened |
| Ella / Él / Usted | habrá reforzado | s/he will have strengthened |
| Nosotras / Nosotros | habremos reforzado | we will have strengthened |
| Vosotras / Vosotros | habréis reforzado | you (plural) will have strengthened |
| Ellas / Ellos / Ustedes | habrán reforzado | they will have strengthened |
How it’s built: Haber in the future (habré, habrás, habrá, habremos, habréis, habrán) plus the past participle reforzado.
The Indicative Conditional Perfect of reforzar is used to talk about something that would have happened in the past but didn’t due to another action. For example, “habría reforzado”, meaning “I would have strengthened”.
In Spanish, the Indicative Conditional Perfect is known as "El Condicional Perfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | habría reforzado | I would have strengthened |
| Tú | habrías reforzado | you would have strengthened |
| Ella / Él / Usted | habría reforzado | s/he would have strengthened |
| Nosotras / Nosotros | habríamos reforzado | we would have strengthened |
| Vosotras / Vosotros | habríais reforzado | you (plural) would have strengthened |
| Ellas / Ellos / Ustedes | habrían reforzado | they would have strengthened |
How it’s built: Haber in the conditional (habría, habrías, habría, habríamos, habríais, habrían) plus the past participle reforzado.
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The Subjunctive Present is used to talk about situations of uncertainty, or emotions such as wishes, desires and hopes. It differs from the indicative mood due to the uncertainty of the events which are being spoken about. For example, “refuerce”, meaning “I strengthen”.
In Spanish, the Subjunctive Present is known as "El Presente de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | refuerce | I strengthen |
| Tú | refuerces | you strengthen |
| Ella / Él / Usted | refuerce | s/he strengthens |
| Nosotras / Nosotros | reforcemos | we strengthen |
| Vosotras / Vosotros | reforcéis | you (plural) strengthen |
| Ellas / Ellos / Ustedes | refuercen | they strengthen |
How it’s built: Yo, tú, ella/él and ellas/ellos change o to ue and z to c (refuerce, refuerces, refuerce, refuercen); nosotros and vosotros change z to c (reforcemos, reforcéis).
Letters in red show where a form differs from the regular pattern.
The Subjunctive Imperfect is used to speak about unlikely or uncertain events in the past or to cast an opinion (emotional) about something that happened in the past. For example, “reforzara”, meaning “I strengthened”.
In Spanish, the Subjunctive Imperfect is known as "El Imperfecto Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | reforzara | I strengthened |
| Tú | reforzaras | you strengthened |
| Ella / Él / Usted | reforzara | s/he strengthened |
| Nosotras / Nosotros | reforzáramos | we strengthened |
| Vosotras / Vosotros | reforzarais | you (plural) strengthened |
| Ellas / Ellos / Ustedes | reforzaran | they strengthened |
How it’s built: Regular: the ellas/ellos preterite, reforzaron, without -ron, plus the -ra endings; nosotros adds an accent (reforzáramos).
The Subjunctive Future is used to speak about hypothetical situations, and actions/events that may happen in the future. For example, “reforzare”, meaning “I will strengthen”.
In Spanish, the Subjunctive Future is known as "El Futuro de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | reforzare | I will strengthen |
| Tú | reforzares | you will strengthen |
| Ella / Él / Usted | reforzare | s/he will strengthen |
| Nosotras / Nosotros | reforzáremos | we will strengthen |
| Vosotras / Vosotros | reforzareis | you (plural) will strengthen |
| Ellas / Ellos / Ustedes | reforzaren | they will strengthen |
How it’s built: Regular: the ellas/ellos preterite, reforzaron, without -ron, plus the -re endings; nosotros adds an accent (reforzáremos).
The Subjunctive Present Perfect is used to describe past actions or events that are still connected to the present day and to speak about an action that will have happened by a certain time in the future. For example, “haya reforzado”, meaning “I have strengthened”.
In Spanish, the Subjunctive Present Perfect is known as "El Pretérito Perfecto de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | haya reforzado | I have strengthened |
| Tú | hayas reforzado | you have strengthened |
| Ella / Él / Usted | haya reforzado | s/he has strengthened |
| Nosotras / Nosotros | hayamos reforzado | we have strengthened |
| Vosotras / Vosotros | hayáis reforzado | you (plural) have strengthened |
| Ellas / Ellos / Ustedes | hayan reforzado | they have strengthened |
How it’s built: Haber in the subjunctive present (haya, hayas, haya, hayamos, hayáis, hayan) plus the past participle reforzado.
The Subjunctive Past Perfect is used to speak about hypothetical situations, and actions/events that occurred before other actions/events in the past. For example, “hubiera reforzado”, meaning “I had strengthened”.
In Spanish, the Subjunctive Past Perfect is known as "El Pretérito Pluscuamperfecto de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | hubiera reforzado | I had strengthened |
| Tú | hubieras reforzado | you had strengthened |
| Ella / Él / Usted | hubiera reforzado | s/he had strengthened |
| Nosotras / Nosotros | hubiéramos reforzado | we had strengthened |
| Vosotras / Vosotros | hubierais reforzado | you (plural) had strengthened |
| Ellas / Ellos / Ustedes | hubieran reforzado | they had strengthened |
How it’s built: Haber in the subjunctive imperfect (hubiera, hubieras, hubiera, hubiéramos, hubierais, hubieran) plus the past participle reforzado.
The Subjunctive Future Perfect is used to speak about something that will have happened if a hypothetical situations occurs in the future. For example, “hubiere reforzado”, meaning “I will have strengthened”.
In Spanish, the Subjunctive Future Perfect is known as "El Futuro Perfecto de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | hubiere reforzado | I will have strengthened |
| Tú | hubieres reforzado | you will have strengthened |
| Ella / Él / Usted | hubiere reforzado | s/he will have strengthened |
| Nosotras / Nosotros | hubiéremos reforzado | we will have strengthened |
| Vosotras / Vosotros | hubiereis reforzado | you (plural) will have strengthened |
| Ellas / Ellos / Ustedes | hubieren reforzado | they will have strengthened |
How it’s built: Haber in the subjunctive future (hubiere, hubieres, hubiere, hubiéremos, hubiereis, hubieren) plus the past participle reforzado.
The Imperative Affirmative is used to give orders and commands, to tell someone to do something. For example, “refuerce”, meaning “(to you formal) strengthen!”.
In Spanish, the Imperative Affirmative is known as "El Imperativo Afirmativo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | - | - |
| Tú | refuerza | (to you) strengthen! |
| Ella / Él / Usted | refuerce | (to you formal) strengthen! |
| Nosotras / Nosotros | reforcemos | let's strengthen! |
| Vosotras / Vosotros | reforzad | (to you plural) strengthen! |
| Ellas / Ellos / Ustedes | refuercen | (to you plural formal) strengthen! |
How it’s built: Tú takes the ella/él present (refuerza); usted, nosotros and ustedes take the subjunctive present (refuerce, reforcemos, refuercen); vosotros swaps the final r of the infinitive for a d (reforzad).
Letters in red show where a form differs from the regular pattern.
The Imperative Negative is used to give orders and commands, telling someone not to do something. For example, “no refuerce”, meaning “(to you formal) don't strengthen!”.
In Spanish, the Imperative Negative is known as "El Imperativo Negativo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | - | - |
| Tú | no refuerces | (to you) don't strengthen! |
| Ella / Él / Usted | no refuerce | (to you formal) don't strengthen! |
| Nosotras / Nosotros | no reforcemos | let's not strengthen! |
| Vosotras / Vosotros | no reforcéis | (to you plural) don't strengthen! |
| Ellas / Ellos / Ustedes | no refuercen | (to you plural formal) don't strengthen! |
How it’s built: No plus the subjunctive present: no refuerces, no refuerce, no reforcemos, no reforcéis, no refuercen.
Letters in red show where a form differs from the regular pattern.
Reforzar is an irregular Spanish verb. In the present tense: yo, tú, ella/él and ellas/ellos change o to ue (refuerzo, refuerzas, refuerza, refuerzan); nosotros and vosotros are regular. It is also irregular in the preterite (reforcé) and present subjunctive (refuerce).
In the present tense (presente), reforzar is conjugated as: yo refuerzo, tú refuerzas, él/ella/usted refuerza, nosotros reforzamos, vosotros reforzáis, ellos/ellas/ustedes refuerzan. The present tense is used To talk about situations, events or thoughts that are happening now or in the near future. It is also used to talk about facts and truths.
In the preterite (pretérito indefinido), reforzar is conjugated as: yo reforcé, tú reforzaste, él/ella/usted reforzó, nosotros reforzamos, vosotros reforzasteis, ellos/ellas/ustedes reforzaron. The preterite is used To talk about actions completed in the past, at a specific point in time.
In the imperfect (pretérito imperfecto), reforzar is conjugated as: yo reforzaba, tú reforzabas, él/ella/usted reforzaba, nosotros reforzábamos, vosotros reforzabais, ellos/ellas/ustedes reforzaban. The imperfect is used To describe regular and repeated actions that happened in the past and descriptions of things you used to do.
In the future tense (futuro simple), reforzar is conjugated as: yo reforzaré, tú reforzarás, él/ella/usted reforzará, nosotros reforzaremos, vosotros reforzaréis, ellos/ellas/ustedes reforzarán. The future tense is used To talk about something that will happen in the future.
In the present subjunctive (subjuntivo presente), reforzar is conjugated as: yo refuerce, tú refuerces, él/ella/usted refuerce, nosotros reforcemos, vosotros reforcéis, ellos/ellas/ustedes refuercen. The present subjunctive is used To talk about situations of uncertainty, or emotions such as wishes, desires and hopes. It differs from the indicative mood due to the uncertainty of the events which are being spoken about.
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