Irregular Spanish Verbs

After taking a few minutes to look at Spanish verbs, you will find that beneath the surface they are full of surprises. Verbs which do not follow the dominant conjugation scheme are called irregular verbs, and they are extremely common in Spanish (just as they are in English). This guide will help prepare you to encounter these tricksters in the wild and understand their irregular ways. First, let’s take a look at how and why Spanish verbs change their forms by comparing them to their English counterparts.


The verbs, they are a-changin’

The form of a verb changes to show who perpetrated the action (the person) and when it occurred (the tense). Spanish uses one extra category of person that corresponds to addressing “you all/you guys” in English. For more on the different person categories and personal pronouns in Spanish, see this guide. Though native speakers often don’t realize it, English has a lot of patterns similar to Spanish that can help us understand and apply the rules of Spanish conjugation. In English, verb inflection can look like this:

PersonPresent tensePresentPast tense
(Singular) continuous (to be +ing) 
First personI sleepI am sleepingI slept
Second personYou sleepYou are sleepingYou slept
Third personHe/She sleepsHe/She is sleepingHe/She slept

A few things to notice in the chart above:

  • Regular English verbs vary little in their specification of person (only adding an -s in the third person in this example).
  • Verbs can combine to include additional information (such as the fact that the action is continuing).
    • Note: In Spanish, the present tense is normally used in place of present continuous.
  • Functional words such as auxiliary verbs (“helping verbs”) serve a grammatical function, but don’t add any semantic content or meaning to the sentence. These are present in both English and Spanish, and combine with a main verb such as sleep.
    • Haber: Just as in English, one of the most common auxiliary verbs in Spanish is haber (“to have/to exist”).
  • Did you notice the drastic change to “to be” compared to “sleep”? In English, “to be” is just like its Spanish equivalent ser in that it:
    • is irregular
    • is one of the most common verbs
    • is used as an auxiliary (only in the passive voice, such as “La ley fue aprobada” (“The law was passed”))
    • changes its stem (How did the “b” and “e” of “be” result in “am,” “are,” and “is”?).

To be or not to be: That is the infinitive

The infinitive form of a verb is its most basic form. You can spot them easily in Spanish because they end in -ar, -ir, -er. The equivalent meaning in English is the same as “to [verb],” so “dormir” is equivalent to “to sleep.”

For regular verbs, the infinitive (infinitivo) lends its stem to its inflected forms in a predictable way. The stem, or raíz (literally “root” in Spanish), is the part that occurs before the -ar, -ir, or -er.

Infinitive: Correr

Stem: Corr-

yo corronosotros corremos
tú corresvosotros corréis
él/ella/ud. correellos/ellas/uds. corren

Irregular verbs can have stem changes that make it difficult to tell which verb is concealed underneath, just like the surprising variety of inflected English forms of “to be” (am/are/is). Consequently, the conjugations for irregular verbs deserve some extra attention and, in the end, just need to be memorized.

To sum up:

  • Good news:
    • Most of the time verbs are conjugated in a standard way, making it easy to change a verb you’ve never seen before into the appropriate form. The vast majority of verbs fall into this category of regular verbs.
  • Not very good news:
    • Irregular verbs fly in the face of expectation and prefer to do their own thing. Conjugations for these verbs don’t follow the usual patterns and sometimes even change their stem, making them virtually unrecognizable to the untrained eye.
  • More good news:
    • Irregular verbs like ser, ir, hacer, haber, poder, and tener are actually some of the most commonly used verbs, meaning that Spanish learners gain valuable exposure to their inflected forms often and can usually memorize the irregularities quickly. In fact, the high frequency of these irregular verbs is what linguists believe has kept their outdated historic inflection patterns around this long.
  • Even more good news:
    • Lingvist’s Spanish course uses machine learning and AI to adapt to your level of Spanish, so whether you’ve already had a lot of exposure to irregular verb forms or the concept is completely new to you, the exercises will be tailored to your level. You’ll also get the opportunity both to learn verbs in context and look over grammar tips to clarify concepts explicitly.

Common Irregular Verbs

Some verbs are more irregular than others. Spanish verbs can undergo a stem change for different “persons,” can change in spelling only in the yo form, or can change almost completely in every different form. Below are a few categorical ways verbs can change, along with a few examples. An exhaustive list of all irregular verbs would be much too long, but this will prepare you for some of the types of diversity you will see. You’ll notice that the majority of irregular verbs end in -er – in fact, about 72% of -er verbs are irregular. It may not be the most enjoyable part of learning a language, but putting in some time to memorize these verb conjugations will make your life much easier.

Changes in the yo form: hacer, estar, and escoger

Changes in only the first-person singular form of a verb are very common. Hacer and estar are examples of a verb for which the only irregularity is in the yo form. Escoger is an example of a verb that follows a rule for changes in the yo form.

Hacer (to do/make)

yo hagonosotros hacemos
hacesvosotros hacéis
él, ella, Ud. haceellos, ellas, Uds. hacen

Estar (to be)

Though ser and estar correspond to one word in English, they are not interchangeable. Estar is used to talk about feelings, rather than the state of things. For example, if you are feeling sick you would say, “Estoy enferma.”

yo estoynosotros estamos
estásvosotros estáis
él, ella, Ud. estáellos, ellas, Uds. están

Escoger (to choose)

For verbs that end in -ger or -gir, the g changes to a j in the yo form.

yo escojonosotros escogemos
escogesvosotros escogéis
él, ella, Ud. escogeellos, ellas, Uds. escogen

Stem changes ease pronunciation: tener and poder

Notice how the stem changes for tener and poder enable more efficient pronunciation. Certain sounds are phonetically “closer” to pronounce and therefore easier to transition between. Over time, words can transform to become easier to pronounce. If tener was conjugated following the standard rules, tú tenes would end up sounding a lot like tú tienes.

Luckily, in a nearly phonetic language like Spanish, these pronunciation changes are reflected in the spelling. This is a rare feature to find in a language, which seriously benefits Spanish learners. If you’re better at remembering what you’ve read, you can memorize the written form and sound it out following the rules of Spanish pronunciation. If you’re an auditory learner, you can say the word out loud to yourself and be reminded of how to spell it. Check out this page on Spanish podcasts for opportunities to listen to native speakers’ pronunciation.

The irregular forms of tener and poder also follow two similar patterns. In the yo form, they both use a “g.” In the past preterite form, they both change the vowel of their stem to “u.”

Notice that the infinitive stem is present in the nosotros and vosotros forms of these verbs. This is common to irregular verbs, but not always the case.

Tener (to have)

The simple present tense is irregular in all forms except nosotros and vosotros:

yo tengonosotros tenemos
tienesvosotros tenéis
él, ella, Ud. tieneellos, ellas, Uds. tienen

Past preterite tense is irregular in all forms:

yo tuvenosotros tuvimos
tuvistevosotros tuvisteis
él, ella, Ud. tuvoellos, ellas, Uds. tuvieron

Poder (to be able to/can)

The simple present tense is irregular in all forms except nosotros and vosotros:

yo puedonosotros podemos
puedesvosotros podéis
él, ella, Ud. puedeellos, ellas, Uds. pueden

Past preterite tense is irregular in all forms:

yo pudenosotros pudimos
pudistevosotros pudisteis
él, ella, Ud. pudoellos, ellas, Uds. pudieron

Person and tense changes: ser (to be) and ir (to go)

As we said above, verbs change to reflect the who and the when. Some verbs, like ser and ir, are extra irregular and transform not only depending on person, but also depending on tense. You’ll notice that the simple future tense includes the whole infinitive plus a pattern of endings.

The past preterite refers to an action that has been completed in the past and is not ongoing or is not habitual. In contrast, the simple past tense is similar to the function of the word “been” to describe a continuous action, such as “I have been attending.”

The past preterite forms of ser and ir are identical, which may seem confusing, but this is usually easily decipherable from the context. On the bright side, it’s one less conjugation table you need to learn!

Ser (to be)

Simple present tense (“I am”):

yo soynosotros somos
eresvosotros sois
él, ella, Ud. esellos, ellas, Uds. son

Simple past tense / imperfect (“I have been”):

yo eranosotros éramos
erasvosotros erais
él, ella, Ud. eraellos, ellas, Uds. eran

Past preterite (“I was”):

yo fuinosotros fuimos
fuistevosotros fuisteis
él, ella, Ud. fueellos, ellas, Uds. fueron

Simple future (“I will”):

yo serénosotros seremos
serásvosotros seréis
él, ella, Ud. seráellos, ellas, Uds. serán

Ir (to go)

Simple present tense (“I go”):

yo voynosotros vamos
vasvosotros vais
él, ella, Ud. vaellos, ellas, Uds. van

Simple past tense / imperfect (“I have been going”):

yo ibanosotros íbamos
ibasvosotros ibais
él, ella, Ud. ibaellos, ellas, Uds. iban

Past preterite (“I went”):

yo fuinosotros fuimos
fuistevosotros fuisteis
él, ella, Ud. fueellos, ellas, Uds. fuiste

Simple future (“I will go”):

yo irénosotros iremos
irásvosotros iréis
él, ella, Ud. iráellos, ellas, Uds. irán

Auxiliary and impersonal: haber

Haber (to have / to exist)

Haber is the most common auxiliary verb in Spanish, meaning that you’ll see it “helping” a lot of main verbs to express a specific meaning.

It can be similar to the auxiliary have in English, as in:

I have been studying Spanish for two years. Yo he estudiado español durante dos años.

It can also be used in temporal phrases, like the English word ago.

Two years ago I went to Spain. Yo fui a España hace dos años.

You’ll also see it used similarly to “there + to be” in English, which is called its impersonal usage.

There are many books. Hay muchos libros.

This usage is called impersonal because the verb doesn’t have a subject to conjugate for, just as there is no specific person or thing that has the property of “having/being” the “many books” in the example of above. The books simply exist. You can therefore see how this ties into haber’s secondary meaning, “to exist.” You do not need to inflect hay according to the number of objects as you do in English, however.

There is a book. Hay un libro.

yo henosotros hemos
hasvosotros habéis
él, ella, Ud. ha (impersonal: hay)ellos, ellas, Uds. han

Memorize with Flash-Charts

Looking for a way to work Spanish study into your daily routine?

Write out conjugation charts on separate pieces of paper and alternate covering them with tape or sticky notes to quiz yourself – just like flashcards. Try putting one verb conjugation chart per week in a place that you habitually spend some time, like on your kitchen cabinets or your bathroom mirror, so that you can look it over while washing dishes or brushing your teeth. Halfway through the week, try covering up the conjugated forms with tape or a sticky note so you can quiz yourself. Practice Spanish at home by downloading the Lingvist app on your computer or cell phone.