How to Say "to assert" in Spanish
The most common Spanish word for “to assert” is “mantener” — use 'mantener' when you want to express that someone is upholding or defending a particular statement or belief, often in the face of potential doubt or opposition..
mantener
/man-teh-NEHR//manteˈneɾ/
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).
sostener
soh-steh-NEHR/sosteˈneɾ/
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 vs. Sostener
Related Translations
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