Present Tense Conjugation of O-UE Stem‐Changing Verbs
Some verbs in Spanish do not follow the regular verb patterns of conjugation, changing a vowel in the stem. Such verbs are called stem-changing verbs. These verbs have all the regular endings but have a change occur in the stem of the verb in certain forms. Stem-changing verbs could be –ar, –er, or –ir verbs.
The second most common type of stem change that occurs in Spanish verbs is o to ue. For verbs in this group, the letter o in the stem of the infinitive will change to ue in all forms except nosotros/nosotras and vosotros/vosotras.
Look at how the o-ue verb dormir ("to sleep") changes forms:
| Subject | Verb | Meaning |
| yo | duermo | I sleep |
| tú | duermes | you sleep |
| él ella usted |
duerme | he sleeps she sleeps you (formal) sleep |
| nosotros nosotras |
dormimos | we sleep we sleep |
| vosotros vosotras |
dormís | you (plural) sleep you (plural) sleep |
| ellos ellas ustedes |
duermen | they sleep they sleep you (formal, plural) sleep |
Here are some other o-ue stem-changing verbs:
almorzar - to have lunch
contar - to tell or to count
costar - to cost
mostrar - to show
poder - to be able to
recordar - to remember
volar - to fly
volver - to return
Now that you know the pattern of a o-ue stem-changing verb, you could form the present tense of any other o-ue verb:
Puedo traducir esta frase. - I can translate this phrase.
¿Cuántas horas duermes? - How many hours do you sleep?
Usted recuerda su número de teléfono. - You (formal) remember her phone number.
Nosotros mostramos la escuela al niño. - We show the school to the child.
Vosotros volvéis a las siete. - You (plural) come back at seven.
Ellos vuelan en el cielo. - They fly in the sky.
