The infinitive is the most basic verb form in all languages. In English, the verb is always preceded by the preposition “to” as in “to speak,” “to read,” or “to write.” In Spanish, infinitives consist of only one word and are separated into three different conjugation sets according to their endings, -AR, -ER, and -IR such as “hablar,” “leer,” and “escribir.”

Verbs in the infinitive form indicate what an action is, but do not indicate anything about who is doing the action or at what point in time the action is taking place. Most verb tenses use a form of the infinitive as the stem for their conjugations. In general, for regular verbs, you simply need to remove the infinitive ending to find the stem, and then you can the add tense’s endings.

Finding the Stem from an Infinitive

-AR Verbs

There are more -AR verbs than the other two categories. There are also fewer irregular -AR verbs than -ER and -IR verbs. Some examples of common -AR infinitives and their stems are:

infinitive definition stem
buscar to look for busc-
cantar to sing cant-
comprar to buy compr-
escuchar to listen to escuch-
extrañar to miss/to yearn for extrañ-
hablar to speak habl-
llamar to call llam-
llenar to fill llen-
llevar to carry llev-
mirar to watch mir-
visitar to visit visit-

-ER Verbs

-ER verbs make up the second largest group of infinitives in Spanish. Some common examples of -ER infinitives are:

infinitive definition stem
beber to drink beb-
comer to eat com-
comprender to understand comprend-
correr to run corr-
creer to believe cre-
deber to owe deb-
leer to read le-
meter to put into met-
romper to break romp-
vender to sell vend-

-IR Verbs

-IR verbs are the smallest group of Spanish infinitives. Some examples of common -IR verbs are:

infinitive definition stem
abrir to open abr-
asistir to attend asist-
cubrir to cover cubr-
escribir to write escrib-
incluir to include inclu-
pedir to order ped-
permitir to allow permit-
recibir to receive recib-
servir to serve serv-
vivir to live viv-

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Category: verbs | Keywords: stems, conjugation