StemChangers in the Preterit

An ‐ ir verb that undergoes a stem change in the present tense will undergo a stem change in the preterit in the third person forms (él, ella, usted, ellos, ellas, and ustedes). Any ‐ir verb that undergoes an o>ue stem change in the present tense undergoes an o>u stem change in the preterit. Table demonstrates the preterit patterns for morir (to die), an ‐ir verb that undergoes an o>ue stem change in the present tense. The verb dormir (to sleep) is conjugated in exactly the same manner.

There are several ‐ir verbs that undergo an e>ie stem change in the present tense. Any ‐ir verb that undergoes an e>ie stem change in the present tense undergoes an e>i stem change in the preterit in the third person forms (él, ella, usted, ellos, ellas, and ustedes). Table represents the conjugation chart for all the verbs in the list that follows. Notice that, just as in the present tense, it is the second e in preferir (to prefer) that undergoes a change.


Common verbs conjugated like preferir in the preterit tense:

An ‐ ir verb that undergoes an e>i stem change in the present tense will also undergo an e>i stem change in the preterit, but only in the third person forms (él, ella, usted, ellos, ellas, and ustedes). The verbs that follow Table are all conjugated like servir (to serve).

Common verbs conjugated like servir in the preterit tense: