Quick Answer
Spanish irregular present tense verbs fall into various categories: verbs with irregular yo forms in the present indicative, stem-changing verbs, spelling-change verbs, and verbs that are irregular in all forms.
Irregular Yo
Some present tense yo conjugations undergo spelling changes or are irregular.
Verbs with Spelling Changes in the Yo Form
Verbs that end in -guir, -ger, or -gir undergo a spelling change in their present tense yo forms.
For verbs that end in -guir, the yo form ends in go.
For verbs that end in -ger or -gir, the g in the yo form changes to a j.
Here are examples of verbs that have yo spelling changes.
Spanish Infinitive English Infinitive Yo Form
extinguir
to extinguish
extingo
dirigir
to direct
dirijo
escoger
to choose
escojo
exigir
to demand
exijo
recoger
to pick up
recojo
Verbs with Irregular Yo Forms
The following verbs have irregular yo forms. The other present tense forms of these verbs follow the patterns for regular -ar, -er, and -ir verbs.
Here are examples of verbs with irregular yo spelling changes.
Spanish Infinitive English Infinitive Yo Form
caber
to fit
quepo
caer
to fall
caigo
conocer
to know
conozco
dar
to give
doy
hacer
to do/make
hago
poner
to put
pongo
saber
to know
sé
salir
to leave/to go out
salgo
traducir
to translate
traduzco
traer
to bring
traigo
valer
to be worth
valgo
ver
to see
veo
Most verbs that end in -cer or -ucir have irregular present tense yo forms.
Prefixes Count
Verbs made of up the above forms plus a prefix are also irregular in the yo form. Check out these examples.
Spanish English Yo Form
componer
to compose
compongo
deshacer
to undo
deshago
disponer
to make available
dispongo
distraer
to distract
distraigo
proponer
to propose
propongo
rehacer
to redo
rehago
reponer
to put back
repongo
suponer
to suppose
supongo
Irregular in All Forms
There are a number of verbs that have irregular forms other than the yo form. These include stem-changing verbs, spelling-change verbs, and verbs that are considered truly irregular.
Four of the most frequently-used verbs in Spanish (ser, estar, ir, and haber) are irregular. The present indicative conjugations for each are given below.
Irregular Conjugations
Ser and Estar
Subject ser (to be) estar (to be)
yo
soy
estoy
tú
eres
estás
usted, él, ella
es
está
nosotros
somos
estamos
vosotros
sois
estáis
ustedes, ellos, ellas
son
están
Ir and Haber
Subject ir (to go) haber (to have)
yo
voy
he
tú
vas
has
usted, él, ella
va
ha
nosotros
vamos
hemos
vosotros
vais
habéis
ustedes, ellos, ellas
van
han
