Verbos con cambio ortográfico i > y (pretérito indefinido)

Stem-changing Spanish i>y verbs in the simple past tense

Written by qualified Spanish expert Inma Sánchez BA
Last updated: 2017-10-13
Spanish verbs ending in -uir undergo a change when they are conjugated in the simple past.
The -i- changes to -y- but it only affects the 3rd person singular and plural. 

For example: 
Construir (to build) → construyó/ construyeron
Note: Oir (to hear) is another verb affected by this change despite not ending in -uir.

To see a list of verbs affected by this irregularity go to List of Spanish irregular -uir verbs (i > y) in the present and past tenses.

Lessons with more detail on Verbos con cambio ortográfico i > y (pretérito indefinido)

Conjugate -uir verbs in the preterite tense in Spanish (El Pretérito Indefinido)
Conjugate leer, creer and proveer in the preterite tense in Spanish (El Pretérito Indefinido)
Conjugate oír in the preterite tense in Spanish (El Pretérito Indefinido)
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