Español — Irregular present indicative
Some very common Spanish verbs do not follow the regular present-tense endings. The largest group is irregular only in the yo form (hago, pongo, salgo), while a few verbs (ser, estar, ir, haber) are irregular throughout. This is different from stem-changing verbs, which alter the vowel in the stressed forms.
How it works
Yo-form irregulars keep the regular endings in every other person: from tener you get tengo, but tú tienes, nosotros tenemos. The change appears only in yo (hago, pongo, salgo, vengo, conozco, doy, sé, veo, oigo). Fully irregular verbs like ser (soy, eres, es, somos, sois, son) or ir (voy, vas, va, vamos, vais, van) change across the whole paradigm.
Examples
| Infinitive | yo form | Full present (yo, tú, él, nosotros, vosotros, ellos) |
|---|---|---|
| hacer | hago | hago, haces, hace, hacemos, hacéis, hacen |
| poner | pongo | pongo, pones, pone, ponemos, ponéis, ponen |
| salir | salgo | salgo, sales, sale, salimos, salís, salen |
| tener | tengo | tengo, tienes, tiene, tenemos, tenéis, tienen |
| venir | vengo | vengo, vienes, viene, venimos, venís, vienen |
| conocer | conozco | conozco, conoces, conoce, conocemos, conocéis, conocen |
| ser | soy | soy, eres, es, somos, sois, son |
| ir | voy | voy, vas, va, vamos, vais, van |
Good to know
Don't confuse yo-form irregulars with stem-changing verbs. tener has both features: irregular yo (tengo) plus the e→ie stem change (tú tienes). But conocer only changes in yo (conozco); the rest is regular (conoces, not conieces). And note that estar (estoy, estás, está, estamos, estáis, están) and haber (he, has, ha, hemos, habéis, han) are irregular but not yo-only, while sé (from saber) and doy (from dar) are irregular only in yo.