Inklingo

How to Say "to assert" in Spanish

English → Spanish

afirmar

ah-fear-MAHRa.fiɾˈmaɾ

verbA2formal
Use 'afirmar' when you are stating something as a fact, often in a more formal or definitive way.
A person with a cheerful expression nodding their head in agreement.

Examples

Afirmó que había estado allí.

He affirmed that he had been there.

El testigo afirmó la verdad de su declaración.

The witness confirmed the truth of his statement.

—¿Estás seguro? —Afirmativo, estoy seguro.

—Are you sure? —Yes, I'm sure.

Saying yes firmly

In informal Spanish, people often say '¡Afirmativo!' (affirmative) or just 'Afirm' as a casual way to say yes, similar to 'yeah!' in English.

Confusing afirmar with afirmar

Mistake: “Using 'afirmar' when you mean 'to make something firm physically'”

Correction: Use 'asegurar' or 'fijar' for the physical meaning (to secure/attach something).

sostener

soh-steh-NEHRsosteˈneɾ

verbB2
Choose 'sostener' when someone is stating something strongly, often when defending a position or belief.
A person standing confidently on a small hill, holding a bright red sphere high above their head.

Examples

El presidente sostiene que la economía mejorará pronto.

The president maintains (or asserts) that the economy will improve soon.

Ella sostuvo su argumento a pesar de la crítica.

She upheld her argument despite the criticism.

Los científicos sostienen la teoría del calentamiento global.

The scientists support (or uphold) the theory of global warming.

Common Structure

When used to assert an idea, 'sostener' is often followed by 'que' and a statement in the indicative mood (normal verb form), since it expresses certainty: 'Sostengo que tienes razón' (I maintain that you are right).

mantener

man-teh-NEHRmanteˈneɾ

verbB2
Use 'mantener' when someone is sticking to or defending a claim or opinion they have previously stated.
A person standing firmly and calmly on a small, stable stone block while several other figures nearby gesture in disagreement.

Examples

El científico mantiene que su teoría es correcta.

The scientist maintains that his theory is correct.

A pesar de la evidencia, el acusado mantuvo su inocencia.

Despite the evidence, the defendant maintained his innocence.

Stating a Belief

This use of 'mantener' is almost always followed by 'que' to introduce the belief or statement you are holding onto. For example, 'Mantengo que es la mejor opción' (I maintain that it's the best option).

Afirmar vs. Sostener/Mantener

Learners often confuse 'afirmar' with 'sostener' or 'mantener'. Remember that 'afirmar' is a more direct statement of fact, while 'sostener' and 'mantener' imply defending a claim or opinion, often in the face of doubt.

Related Translations

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