There are a lot of irregular verbs in the Preterit Tense. Some are completely irregular and follow no pattern, so they must be memorized. Others have a stem-change in the 3rd-person. Another group makes orthographic changes in the 1st-person singular form. The last group changes their stems, and add different endings.
Group #1 – Completely Irregular Verbs
These verbs are irregular, and follow no set pattern. They must be memorized. Notice that “ser” and “ir” have the exact same conjugation in the Preterit. The context of the sentence will tell you which verb is being used.
| verbs included in this group | |
| dar | to give |
| ver | to see |
| ser | to be |
| ir | to go |
Example conjugations: | |
| dar (to give) | |
| di | dimos |
| diste | disteis |
| dio | dieron |
| ver (to see) | |
| vi | vimos |
| viste | visteis |
| vio | vieron |
| ser (to be) & ir (to go) | |
| fui | fuimos |
| fuiste | fuisteis |
| fue | fueron |
Group #2 – Verbs with an orthographic change
All verbs that end in “gar”, “car”, and “zar” have an orthographic change .
Verbs that end in “gar” add a “u” before the “é”
Verbs that end in “car” change the “c” to a “qu”
Verbs that end in “zar” change the “z” to a “c”
| verbs included in this group | |
| llegar | to arrive |
| jugar | to play (a game) |
| buscar | to search for |
| practicar | to practice |
| empezar | to begin |
| rezar | to pray |
Example conjugations: | |
| llegar (to arrive) | |
| llegué | llegamos |
| llegaste | llegasteis |
| llegó | llegaron |
| buscar (to search for) | |
| busqué | buscamos |
| buscaste | buscasteis |
| buscó | buscaron |
| empezar (to begin) | |
| empecé | empezamos |
| empezaste | empezasteis |
| empezó | empezaron |
Group #3 – Ir stem-changing verbs
Stem-changing verbs that end in -ir will make a change in the Preterit Tense. However, these changes will take place only in the 3rd-person singular and plural forms.
Ir verbs that change O->UE in the Present will change O->U in the Preterit
Ir verbs that change E->IE in the Present will change E->I in the Preterit
Ir verbs that change E->I in the Present will also change E->I in the Preterit
| verbs included in this group | |
| dormir | O->UE Stem-Changer |
| morir | O->UE Stem-Changer |
| mentir | E->IE Stem-Changer |
| sentir | E->IE Stem-Changer |
| pedir | E->I Stem-Changer |
| seguir | E->I Stem-Changer |
Example conjugations: | |
| dormir (to sleep) | |
| dormí | dormimos |
| dormiste | dormisteis |
| durmió | durmieron |
| mentir (to lie) | |
| mentí | mentimos |
| mentiste | mentisteis |
| mintió | mintieron |
| pedir (to ask for, to request) | |
| pedí | pedimos |
| pediste | pedisteis |
| pidió | pidieron |
Group #4 – Verbs that add a “y”
Verbs that end in 2 vowels before the “r”, will add a “y” in the 3rd-person singular and plural forms. This is done so that there will not be 3 vowels in a row. Notice how the endings switch to “ó” and “eron” for the 3rd person forms in this group.
*The verbs listed below that do not end in “uir” also add an accent to the “i” in the tú, nosotros, & vosotros forms. This means there will be an accented “i” in all 1st & 2nd-person forms in the Preterit.
| verbs included in this group | |
| contribuir | to contribute |
| incluir | to include |
| oír* | to hear |
| caer* | to fall |
| traer* | to bring |
| creer* | to believe |
| leer* | to read |
| poseer* | to possess |
Example coniugations: | |
| oír (to hear) | |
| oí | oímos |
| oíste | oísteis |
| oyó | oyeron |
| creer (to believe) | |
| creí | creímos |
| creíste | creísteis |
| creyó | creyeron |
Verbs With Changing Stems (Group 1)
These verbs change their stem in the Preterit Tense only. They also use a special set of endings as well.
First of all, here are the irregular endings used for these verbs:
| Singular | Plural | |
| 1st person | -e | -imos |
| 2nd person | -iste | -isteis |
| 3rd person | -o | -ieron |
| verb | stem in the preterit tense |
| andar | anduv- |
| estar | estuv- |
| tener | tuv- |
| caber | cup- |
| haber | hub- |
| poder | pud- |
| poner | pus- |
| saber | sup- |
| hacer* | hic- |
| querer | quis- |
| venir | vin- |
| *The 3rd-person singular form of hacer is “hizo” instead of “hico” Example conjugations: | |
| tener | |
| tuve | tuvimos |
| tuviste | tuvisteis |
| tuvo | tuvieron |
| querer | |
| quise | quisimos |
| quisiste | quisisteis |
| quiso | quisieron |
Verbs With Changing Stems (Group 2)
These verbs also change their stem in the Preterit Tense, and they also use a special set of endings as well. Notice that they are the same as the group above, except for the 3rd-person plural.
Here are the irregular endings used for these verbs:
| Singular | Plural | |
| 1st person | -e | -imos |
| 2nd person | -iste | -isteis |
| 3rd person | -o | -eron |
| verb | stem in the preterit tense |
| decir | dij- |
| traer | traj- |
| traducir | traduj- |
| producir | produj- |
| reducir | reduj- |
| Example conjugation: | |
| decir | |
| dije | dijimos |
| dijiste | dijisteis |
| dijo | dijieron |