Spanish Stem-Changing Verbs
Radical-Changing Verbs (Present Tense)
Verbs that undergo a vowel change in their stem (e->ie, o->ue, e->i) in all present tense forms except nosotros/vosotros.
Radical-changing (or stem-changing) verbs in Spanish undergo a vowel shift in the stressed stem syllable in the present tense. The three main patterns are: e->ie (e.g., pensar -> pienso), o->ue (e.g., poder -> puedo), and e->i (e.g., pedir -> pido). These changes occur in the singular forms (yo, tú, él/ella) and the third-person plural (ellos/ellas), forming a 'boot' shape on conjugation tables. The first-person and second-person plural forms (nosotros, vosotros) remain regular.
Examples
Yo pienso que es una buena idea.
I think it is a good idea.
Nosotros pensamos en las vacaciones.
We are thinking about the holidays.
Ellos no pueden venir hoy.
They cannot come today.
Related terms
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