Present Tense of o -> ue Stem-changing Verbs

Present Tense of o -> ue Stem-changing Verbs

a) Root-changing or Stem-changing verbs undergo a change in the stem or root of the verb in the present indicative. When last stem vowel of the verb is a stressed o, the stem vowel o changes to ue

b) Since the stem vowel is not stressed in the first and second person plural forms, there is no stem change. That is, the o does not change to ue.

Volver (to return)
Pronombre Pronoun Raíz Stem Pronombre Pronoun Raíz Stem

Yo vuelvo I return Nosotros, Nosotras volvemos we return
Tú vuelves you return ustedes vuelven you return
El, Ella, Usted (Ud.) vuelve he/ she returns Ellos, Ellas vuelven they return

c) Notice that the verb changes occur only in the first, second and third persons singular and third person plural. To remember these changes when conjugating stem changing verbs, use the formula 1-2-3-6.

d) Since the subject is not expressed, the verb llover is only conjugated in the third person singular.

Examples
Llueve mucho y no podemos salir. It rains a lot and we can't go out.

e)
1. Generalmente, el verbo "costar" sólo se usa en tercera persona singular y plural.
Ejemplo:
No cuesta mucho aprender el español.
Las verduras cuestan mucho. Generally, the verb "costar" is only used in the third person singular and plural.

Example:

It does not cost too much to learn Spanish.

The vegetables cost too much.

2. El verbo "jugar" cambia la vocal de su raíz de "u" a "ue". Normalmente es seguido por la preposición "a" antes de un deporte. The verb "jugar" changes its stem vowel "u" to "ue". It is usually followed by the preposition "a" before a sport.

Jugar (to play)
Pronombre Pronoun Raíz Stem Pronombre Pronoun Raíz Stem
Yo juego I play Nosotros, Nosotras jugamos we play
Tú juegas you play ustedes juegan you play
El, Ella, Usted (Ud.) juega he/she plays Ellos, Ellas juegan they play