With this group of verbs, the stem vowel e changes to an ie in all of the forms except the first and second person plural.

Comenzar (to start, to begin)
	Singular	Plural
1a	comienzo	comenzamos
2a	comienzas	comenzáis
3a	comienza	comienzan

Note that the nosotros and vosotros forms do not change their ‘e’ to ‘ie’, because the stress in those forms falls on the next syllable.

And remember that the stem-changing vowel does not affect the personal ending for the verb, which depends on who the subject is and whether the verb is in the -AR, -ER, or -IR conjugation group. Here’s an example of a familiar -ER verb that has the e-ie stem change:

Querer (to want)
	Singular	Plural
1a	quiero	queremos
2a	quieres	queréis
3a	quiere	quieren

Venir

The verb venir means “to come”, and it has the same irregularities as tener when conjugated in the present tense. But it doesn’t have so many idiomatic uses!

venir (to come)
	singular	plural
1a	yo vengo	nosotros venimos
2a	tú vienes	vosotros venís
3a	él viene ella viene usted viene	ellos vienen ellas vienen ustedes vienen

• Ellos vienen a la universidad todos los días. (They come to the university every day.)
• ¿A qué hora vienes a la clase de español? (At what time do you come to Spanish class?)