How To Conjugate Irregular Verbs In Spanish

In our article “How to Conjugate Verbs in Spanish [insert a link here], we demonstrated how the Spanish infinitive (-ar, -er, -ir) is the basis of using a verb to demonstrate action, who is doing the action, and when the action is accomplished—in other words, conjugated.

Regular Spanish verbs follow a consistent pattern in their conjugations, depending on their infinitive form. An irregular Spanish verb does not. Can you tell if a Spanish verb is irregular by looking at its infinitive? The bad news is that you cannot. You must learn those verbs as you encounter them.

It’s the same in English. You picked up irregular verbs as you learned the language. You learned to say, “I caught the ball,” as the irregular form of the verb “catch.” We smile when we hear a four-year-old struggling with irregular verbs, but when we learned English verb grammar, we threw (not “throwed”) away the trappings of youth in favor of proper English.

The good news is that (1) the most common Spanish irregular verbs are used frequently, and (2) Spanish irregular verbs often follow patterns in their irregular conjugation and spelling changes.

The not-so-good news is that there are a number of additional irregularities—for example, stem changing verbs—which, again, the learner has to learn as they are encountered. But, getting back to the better news, in Spanish you can learn irregular verb patterns and apply those patterns to a set of verbs.

What follows is a description of irregular verb patterns with a few examples. To access a complete conjugation chart for over 1,200 Spanish verbs, log on to Reverso Conjugation.

Concentrate On The Most Common Irregular Verbs

Below Is A List Of The 10 Most Common Irregular Spanish Verbs:

*estar – to be (estoy = I am)

*ser – to be (soy = I am)

dar – to give (doy = I give)

ir – to go (voy = I go)

decir – to say (digo = I say)

hacer – to make (hago = I do)

poder – to be able to (puedo = I can)

saber – to know (sé = I know)

tener – to have (tengo = I have)

haber – auxiliary “to be/to have” (used in compound verb tenses) (he = I have)

*For more insight on the differences between the verbs ser and estar, see this article .

You may have noticed some similarities in the first-person forms of the above common Spanish irregular verbs. There are more similarities, and they include stem changes and spelling patterns in irregular verbs. 

Stem Changing Verbs

You will recall that the verb stem is the part of the verb before the -ar, -er, and -ir infinitive form. Thus, habl- is the verb stem for the verb hablar. Verb stem changes occur in many Spanish verbs in the present tense, and each verb must be learned individually.

An example of a stem-changing verb would be the verb poder (to be able). The spelling of the verb stem pod– changes to pued-. The verb stem spelling change occurs in the singular first (puedo), second (puedes), and third persons singular and plural (puede, pueden). The first- and second-persons plural keep the original verb stem (podemos, podéis).

The five types of present tense stem changing verbs in Spanish with examples are:

• O to UE – poder (see explanation in the preceding paragraph)
• E to IE – querer (to wish): stem changes to quier-
• I to IE change – adquirir (to acquire): stem changes to adquie–
• E to I change – repetir (to repeat): stem changes to repit–
• U to UE change – jugar (to play): stem changes to jue– (Good news! This is the only commonly-used Spanish verb with the stem spelling change.)

For a listing of common Spanish stem-changing verbs, log on to this SpanishDict.com lesson.

Spelling Changes In Spanish Verb Conjugations To Maintain Verb Pronunciation Consistency: 

A Spanish verb ending in

For example, the verb

Changes its spelling in

To

-car

buscar (to look for)

preterit first person and all forms of the subjunctive mood

busqué (I looked) / busque, es, etc., for the subjunctive)

-gar

llegar (to arrive)

preterit first person and all forms of the subjunctive mood

llegué (I arrived)/ llegue, -es, -etc. for the subjunctive

-zar

abrazar (to embrace)

preterite first person and all forms of the subjunctive

abracé (I embraced) / abrace, -es, etc. for the subjunctive

-zir

zurzir (to mend)

all verb tenses

substitute the letter “c” for the “z” before “e” and “i” endings

-guar

averiguar (to find out)

preterite first person and all forms of the subjunctive

averigüé (I found out) / averigüe, etc. for the subjunctive

-cer

conocer (to know)

present tense, first person and subjunctive

conozco (I know) and conozca, -as, etc. for the subjunctive

-guir

distinguir ( to distinguish)

present tense, first person and subjunctive mood

distingo (I distinguish) / distinga, -as, etc. for the subjunctive