-er verb irregular · c>zc C1 · Advanced

Conjugate fortalecer in Spanish

to strengthen

fortalecer is an irregular -er verb ranked #2123 among the most common Spanish verbs. For example: "El ejercicio fortalece los músculos." (Exercise strengthens the muscles.). Use the tables below for full conjugation across all 7 tenses.

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⚡ Irregular verb — fortalecer (c>zc) does not follow standard -er patterns. Pay close attention to the stems in each tense.

Describes current actions, habits, and general truths. The most frequently used tense — master it first.

Pronoun Conjugation
yo fortalezco *
fortaleces
él/ella/Ud. fortalece
nosotros fortalecemos
vosotros fortalecéis
ellos/ellas/Uds. fortalecen
Example

El ejercicio fortalece los músculos.

Exercise strengthens the muscles.

Describes completed past actions with a clear start and end. Key signals: ayer, el lunes pasado, de repente.

Pronoun Conjugation
yo fortalecí
fortaleciste
él/ella/Ud. fortaleció
nosotros fortalecimos
vosotros fortalecisteis
ellos/ellas/Uds. fortalecieron
Example

Ayer yo fortalecí.

Yesterday I strengthen.

Describes habitual past actions, background context, and ongoing states. Key signals: siempre, normalmente, cuando era niño.

Pronoun Conjugation
yo fortalecía
fortalecías
él/ella/Ud. fortalecía
nosotros fortalecíamos
vosotros fortalecíais
ellos/ellas/Uds. fortalecían
Example

Antes yo fortalecía con frecuencia.

Before, I used to strengthen often.

Describes future events and predictions. In everyday speech, ir a + infinitive is often preferred for planned events.

Pronoun Conjugation
yo fortaleceré
fortalecerás
él/ella/Ud. fortalecerá
nosotros fortaleceremos
vosotros fortaleceréis
ellos/ellas/Uds. fortalecerán
Example

Mañana yo fortaleceré.

Tomorrow I will strengthen.

Expresses what would happen under certain conditions — equivalent to "would" in English. Also used for polite requests.

Pronoun Conjugation
yo fortalecería
fortalecerías
él/ella/Ud. fortalecería
nosotros fortaleceríamos
vosotros fortaleceríais
ellos/ellas/Uds. fortalecerían
Example

Si pudiera, yo fortalecería.

If I could, I would strengthen.

Used in clauses expressing wishes, doubt, emotion, or uncertainty — typically after que. Triggers: querer, esperar, dudar, ojalá.

Pronoun Conjugation
yo fortalezca *
fortalezcas *
él/ella/Ud. fortalezca *
nosotros fortalezcamos *
vosotros fortalezcáis *
ellos/ellas/Uds. fortalezcan *
Example

Espero que tú fortalezcas.

I hope that you strengthen.

Used to give commands and direct requests. Affirmative and negative forms differ significantly in Spanish.

Pronoun Conjugation
yo -
fortalece
él/ella/Ud. fortalezca *
nosotros fortalezcamos *
vosotros fortaleced
ellos/ellas/Uds. fortalezcan *
Example

El ejercicio fortalece los músculos.

Exercise strengthens the muscles.

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Example sentences

Common phrases with fortalecer

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