-ar verb irregular · stem-changing o>ue Intermediate

demostrar — Preterite (Pretérito)

to demonstrate / to prove

The preterite conjugation of demostrar (irregular stem-changing o>ue, ranked #131). Describes completed past actions with a clear start and end. Key signals: ayer, el lunes pasado, de repente.

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Pronoun Preterite conjugation
yo demostré
demostraste
él/ella/Ud. demostró
nosotros demostramos
vosotros demostrasteis
ellos/ellas/Uds. demostraron

* Red forms deviate from the regular -ar preterite pattern.

Example sentence

Nosotros demostramos juntos.

We demonstrate together.

Other tenses of demostrar

See full conjugation table for demostrar →

Related verbs

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