Spanish II: Stem‐Changing Verbs in the Present Tense

For the verbs presented so far, the ending is what is irregular. There is, however, a different kind of predictable verb conjugation in which the stem of the verb changes and the endings are normal—even the yo form! The stem of a verb is what is left when you remove the infinitive ending ( -ar, -er, or - ir).

Because the stem of the verb changes, these verbs are called stem-changing verbs, or stem-changers. You must learn each particular verb and remember that it is a stem-changer. It is impossible to identify that a verb is a stem-changer by simply looking at the infinitive unless you recognize a previously learned stem-changer with a prefix.

The hardest part about stem-changers is that you have to memorize the verbs in which stem changes occur. Once you memorize the type of stem change a verb undergoes, the actual patterns of the stem-changing verbs are quite simple; because all the conjugation endings are regular, conjugating these verbs is easy.

For all stem-changers, it is always the stressed syllable that changes. Stem-changing verbs are so common that most dictionaries inform you of the stem change in the entry even before giving the verb's translation.

There are basically three different ways in which the stem of a verb can change in the present tense. The verbs listed below are grouped according to the type of stem change they undergo. When you learn the meanings of the verbs below, memorize what kind of stem change each undergoes as well.

The patterns for stem-changing verbs are very consistent. All forms of the verb will undergo a stem change except for nosotros/nosotras and vosotros/vosotras. The best way to see the patterns is to consider a few examples.

e>ie stem-changers

The most common stem change is e>ie. That means the stressed letter e in the stem of the verb will change to ie in certain forms of the verb. If a verb has two e's in the stem, it will always be the second e that undergoes a stem change. In the lists and charts below, the specific e that changes to ie is underlined.

The verb cerrar is typical of an - ar verb with an e>ie stem change. In Table 1 , the ie is underlined where the stem change occurs. Notice that nosotros/nosotras and vosotros/vosotras do not undergo a stem change.

TABLE 1

Conjugation Chart for the Verb C errar (to Close)

Subject	Verb	Subject	Verb
yo	c ierro	nosotros/nosotras	cerramos
tú	c ierras	vosotros/vosotras	cerráis
él	c ierra	ellos	c ierran
ella	c ierra	ellas	c ierran
usted	c ierra	ustedes	c ierran

All the e>ie stem-changing verbs listed below include the stem change in parentheses after the infinitive. You should remember the verbs with the e>ie as a part of the infinitive in Spanish so that you will be able to conjugate these verbs correctly.

Listed below are some commonly used -ar verbs that undergo an e>ie stem change exactly like that shown in Table 1 .

acertar (e>ie)	to guess, to get correct
apretar (e>ie)	to tighten, to squeeze
atravesar (e>ie)	to cross
cerrar (e>ie)	to close
comenzar (e>ie)	to begin (interchangeable with empezar)
confesar (e>ie)	to confess
despertar (e>ie)	to wake up
empezar (e>ie)	to begin (interchangeable with comenzar)
gobernar (e>ie)	to govern
helar (e>ie)	to freeze
negar (e>ie)	to deny
pensar (e>ie)	to think
quebrar (e>ie)	to break
recomendar (e>ie)	to recommend
remendar (e>ie)	to patch
sentarse (e>ie)	to sit down
temblar (e>ie)	to tremble
tropezar (e>ie) (con)	to stumble, to bump into

Encerrar (e>ie) (to enclose) is a good example of a basic verb that you know ( cerrar) and a prefix ( en-).

The verb perder is a typical - er verb with an e>ie stem change. The forms of this verb presented in Table 2 serve as an example for all the verbs listed below.

TABLE 2

Conjugation Chart for the Verb P erder (to Lose)

Subject	Verb	Subject	Verb
yo	p ierdo	nosotros/nosotras	perdemos
tú	p ierdes	vosotros/vosotras	perdéis
él	p ierde	ellos	p ierden
ella	p ierde	ellas	p ierden
usted	p ierde	ustedes	p ierden

Notice that, in the verbs below, the - er ending is not part of the stem, so perder and querer only have one e in the stem. When verbs like defender and entender have two e's in the stem, the second one, closer to the end, will undergo a stem change. See Table 3 for a sample conjugation chart.

TABLE 3

Conjugation Chart for the Verb Def ender (to Defend)

Subject	Verb	Subject	Verb
yo	def iendo	nosotros/nosotras	defendemos
tú	def iendes	vosotros/vosotras	defendéis
él	def iende	ellos	def ienden
ella	def iende	ellas	def ienden
usted	def iende	ustedes	def ienden

The following list includes common -er verbs that undergo the stem change e>ie.

ascender (e>ie)	to ascend (to go up)
descender (e>ie)	to descend (to go down)
defender (e>ie)	to defend
encender (e>ie)	to light
entender (e>ie)	to understand
perder (e>ie)	to lose
querer (e>ie)	to want

For -ir verbs that undergo the stem change e>ie, all follow the same patterns as the verb mentir in Table 4 . Use this conjugation chart as an example for the forms of the verbs in the list that follows.

TABLE 4

Conjugation Chart for the Verb M entir (to Tell a Lie)

Subject	Verb	Subject	Verb
yo	m iento	nosotros/nosotras	mentimos
tú	m ientes	vosotros/vosotras	mentís
él	m iente	ellos	m ienten
ella	m iente	ellas	m ienten
usted	m iente	ustedes	m ienten

Some of the most common - ir verbs that undergo an e>ie stem change are listed below.

advertir (e>ie)	to advise, to warn
convertir (e>ie)	to convert
hervir (e>ie)	to boil
mentir (e>ie)	to tell a lie
preferir (e>ie)	to prefer
referir (e>ie)	to refer
sentir (e>ie)	to feel, to regret
sugerir (e>ie)	to suggest

Consentir (e>ie) (to consent) is a good example of a basic verb that you know ( sentir) and a prefix ( con-).

Notice that the verb preferir has two e's in the stem. Whenever there are two e's in the stem of a verb, it is the second one that undergoes a stem change. The conjugated forms of preferir are somewhat difficult to picture, so take a good look at Table 5 that follows. When pronouncing these verb forms, remember to say every vowel.

TABLE 5

Conjugation Chart for the Verb Pref erir (to Prefer)

Subject	Verb	Subject	Verb
yo	pref iero	nosotros/nosotras	preferimos
tú	pref ieres	vosotros/vosotras	preferís
él	pref iere	ellos	pref ieren
ella	pref iere	ellas	pref ieren
usted	pref iere	ustedes	pref ieren

Tener and venir are e>ie stem-changers that also have an irregular yo form. You may remember that these two verbs were listed with the -go verbs under the yo irregulars. That is because the yo form of each of these verbs ends in - go; the rest of the forms, however, follow the e>ie stem-changing patterns. These verbs are very common, so be sure to learn the conjugation charts in Table 6 and Table 7 .

TABLE 6

Conjugation Chart for the Verb T ener (to Have)

Subject	Verb	Subject	Verb
yo	tengo	nosotros/nosotras	tenemos
tú	t ienes	vosotros/vosotras	tenéis
él	t iene	ellos	t ienen
ella	t iene	ellas	t ienen
usted	t iene	ustedes	t ienen

TABLE 7

Conjugation Chart for the Verb V enir (to Come)

Subject	Verb	Subject	Verb
yo	vengo	nosotros/nosotras	venimos
tú	v ienes	vosotros/vosotras	venís
él	v iene	ellos	v ienen
ella	v iene	ellas	v ienen
usted	v iene	ustedes	v ienen

The forms for both verbs are very similar, but you should be careful to notice that the nosotros/nosotras and vosotros/vosotras endings are different for venir because it is an - ir verb and tener is an - er verb.

o>ue stem-changers

The second-most common type of stem change that occurs in Spanish verbs is o>ue. Now that you understand how to conjugate stem-changing verbs in general, learning about the verbs with an o>ue stem change will be relatively easy.

Common -ar verbs that undergo a stem change o>ue:

acordar (o>ue)	to agree upon
acostarse (o>ue)	to go to bed
almorzar (o>ue)	to eat lunch
aprobar (o>ue)	to approve
contar (o>ue)	to count, to tell a story
costar (o>ue)	to cost
encontrar (o>ue)	to find
mostrar (o>ue)	to show (interchangeable with demostrar)
probar (o>ue)	to prove
recordar (o>ue)	to remember, to remind
rogar (o>ue)	to pray
sonar (o>ue)	to sound
soñar (o>ue) (con)	to dream
tostar (o>ue)	to toast
volar (o>ue)	to fly

Demostrar (o>ue) is a good example of a basic verb that you know ( mostrar) and a prefix ( de-). The verb demostrar is interchangeable with mostrar because they both mean “to show.”

Common -er verbs that undergo a stem change o>ue:

doler (o>ue)	to ache, to hurt
morder (o>ue)	to bite
mover (o>ue)	to move
poder (o>ue)	to be able
resolver (o>ue)	to resolve
soler (o>ue)	to be accustomed to
volver (o>ue)	to return

Devolver (o>ue) (to return an object, to give something back) and envolver (o>ue) (to wrap up) are good examples of a basic verb that you know ( volver) and different prefixes ( de- and en-).

By now, you understand that a stem-changing verb will have regular verb endings, so Table 8 is the only example of an o>ue stem-changer.

TABLE 8

Conjugation Chart for the Verb M over (to Move)

Subject	Verb	Subject	Verb
yo	m uevo	nosotros/nosotras	movemos
tú	m ueves	vosotros/vosotras	movéis
él	m ueve	ellos	m ueven
ella	m ueve	ellas	m ueven
usted	m ueve	ustedes	m ueven

The following verbs also undergo an o>ue stem change; because they are - ir verbs, however, the nosotros/nosotras ending is - imos.

Common -ir verbs that stem change o>ue:

dormir (o>ue)	to sleep
morir (o>ue)	to die

The verb jugar is usually listed with the o>ue stem-changing verbs because it follows the same pattern. However, you may notice there is no o to change to ue in the verb jugar. It is the only u>ue stem-changer in the Spanish language. Because it means “to play” (a sport or game), it's a popular word in both Spanish- and English-speaking cultures. See Table 9 for the unusual verb forms of jugar.

TABLE 9

Conjugation Chart for the Verb J ugar (to Play)

*Subject*	*Verb*	*Subject*	*Verb*
yo	j uego	nosotros/nosotras	jugamos
tú	j uegas	vosotros/vosotras	jugáis
él	j uega	ellos	j uegan
ella	j uega	ellas	j uegan
usted	j uega	ustedes	j uegan

e>i stem-changers

Here's a test of your grasp of formal logic: All e>i stem-changing verbs are -ir verbs, but not all - ir verbs are e>i stem-changers. Consider the earlier list of e>ie stem-changers; some of them are -ir verbs. This means that when you learn an - ir verb that undergoes a stem change, you have to be careful to remember whether it undergoes an e>ie or e>i stem change. Fortunately, the list of e>i stem-changing verbs is short, and it is true that only - ir verbs can undergo an e>i stem change.

Common e>i stem-changing verbs:

bendecir (e>i)	to bless
colegir (e>i)	to deduce
competir (e>i)	to compete
corregir (e>i)	to correct
decir (e>i)	to say, to tell
despedirse (e>i)	to say goodbye
elegir (e>i)	to elect
freír (e>i)	to fry
gemir (e>i)	to grumble, to groan
maldecir (e>i)	to curse
medir (e>i)	to measure
pedir (e>i)	to request
reír (e>i)	to laugh
repetir (e>i)	to repeat
seguir (e>i)	to follow, to continue
servir (e>i)	to serve
sonreír (e>i)	to smile
vestir (e>i)	to dress

Despedir (e>i) (to fire), impedir (e>i) (to impede, to prevent), and desvestir (e>i) (to undress) are good examples of basic verbs that you know ( pedir and vestir) and a prefix ( des- and im-).

Because all the above verbs are - ir verbs, you only need one example of the conjugation chart for these verbs. All e>i stem-changers will be conjugated like servir in Table 10 .

TABLE 10

Conjugation Chart for the Verb S ervir (to Serve)

Subject	Verb	Subject	Verb
yo	s irvo	nosotros/nosotras	servimos
tú	s irves	vosotros/vosotras	servís
él	s irve	ellos	s irven
ella	s irve	ellas	s irven
usted	s irve	ustedes	s irven