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Spanish 101A

Spanish 101B

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The most important things to remember about stem-changing verbs in the Preterite Past Tense are that:

1) -Ar verbs that stem-change in the present tense (e.g., mostrar, almorzar, pensar and -Er Present tense stem-changing verbs (e.g., Perder, Tener, entender) do not stem-change in any other tenses including the Preterite.

2) -Ir verbs that stem-change in the present tense (e.g. Dormir, Servir, Preferir, etc.) continue to have stem-changes.

  • However, these stem-changes occur only in the 3rd person singular (él, ella, usted) and 3rd person plural (ellos, ellas, ustedes).

  • They follow the same stem-changing pattern they have in the present progressive tense ("-iendo"):

    • The "O-->UE" stem-changers change to "U" as they did with the "-ing" (-iendo) form:
    • Dormir: él está durmiendo, él durmió

    • And the E--->IE and the E--->I change to "I" as they did with the "-ing" (-iendo) form:
    • Servir: Ella está sirviendo cerveza, ella sirvió cerveza.
Yo él, ella, usted nosotros ellos, ellas, ustedes
dormí dormiste durmió dormimos durmieron
(ue, u)
morí moriste murió morimos murieron
(i, i)
serví serviste sirvió servimos sirvieron
(ie, i)
preferí preferiste prefirió preferimos prefirieron
(i, i)
repetí repetiste repitió repetimos repitieron

(i, i)

pedí pediste pidió pedimos pidieron

When you see stem-changing verbs listed in a text book or in a dictionary with vowels in a parenthesis, they are followed by the stem-change in the present tense in parenthesis: Pensar (ie), Entender (ie), Almorzar (ue).

Ir stem-changing verbs have two sets of vowel changes separated by a comma. This indicates first the stem-change in the Present Tense and then the stem-change for all other tenses: Preferir (ie, i) él prefiere (present), él prefirió (preterite)