Question

lets write: preterite tense spelling changes in a sentence
write the correct preterite form of the verb in parenthesis to complete each sentence.

1. la crisis ______ (influir) en la economía.
2. mi madre ______ (conducir) el carro hasta la playa.
3. yo ______ (alcanzar) la cima de la montaña.
4. la directora ______ (sustituir) al profesor enfermo.

Explanation:

All verbs are Spanish -IR stem-changing verbs (o→u or e→i) that require spelling changes in the preterite for third-person singular, first-person singular, and third-person plural forms. We conjugate each to match the subject's number and person.

1. Subject "La crisis" is 3rd-person singular; "influir" changes stem to "influy-" for preterite 3rd sing.
2. Subject "Mi madre" is 3rd-person singular; "conducir" changes stem to "conduj-" for preterite 3rd sing.
3. Subject "Yo" is 1st-person singular; "alcanzar" changes stem to "alcanz-" (regular preterite for 1st sing of -AR verb, no stem change here, just standard conjugation).
4. Subject "La directora" is 3rd-person singular; "sustituir" changes stem to "sustituy-" for preterite 3rd sing.

Answer:

1. influyó
2. condujo
3. alcancé
4. sustituyó