15.1 Stem-Changers
In the preterite, some of the most common verbs take on completely new stems. These aren't small tweaks—the stems change so dramatically that the verbs can look and sound quite different from their infinitives. The good news is that these are high-frequency verbs, so you'll encounter them constantly, and VerbMaster has plenty of practice to help you master them.
The process is the same as always: break the infinitive in half and swap the stem for a new one. For example, hacer (to do) becomes HIC‑, tener (to have) becomes TUV‑, and decir (to say) becomes DIJ‑. Then you add a special set of preterite endings (shown after the charts below).
Let's see these in action:
Here are the endings used by all of these stem-changing preterite verbs. Notice that the yo and él/ella/usted forms have no written accents—unlike regular preterite endings:
| yo | -e |
| tú | -iste |
| él/ella/Ud. | -o |
| nosotros/as | -imos |
| vosotros/as | -isteis |
| ellos/ellas/Uds. | -ieron |
15.2 More Stem-Change Verbs
Here are more verbs that follow this same pattern—each one swaps its stem in the preterite and uses the endings from Section 15.1:
Stem-Changing Verbs in the Preterite
| estar → estuv-(to be) | haber → hub-(to have) |
| poder → pud-(to be able to) | querer → quis-(to want) |
| saber → sup-(to know) | poner → pus-(to put, to set) |
| venir → vin-(to come) | mantener → mantuv-*(to maintain) |
| obtener → obtuv-*(to obtain) | suponer → supus-*(to suppose) |
| traer → traj-(to bring) | andar → anduv-(to walk) |
* Notice that some of these verbs are prefixed forms of other verbs on the list. A prefixed verb is just a root verb with extra letters stuck on the front—and those extra letters never change. The root verb does all the conjugating:
- man + tener = mantener → man + tuv‑ = mantuv‑
- ob + tener = obtener → ob + tuv‑ = obtuv‑
- su + poner = suponer → su + pus‑ = supus‑
Learn one root verb's pattern and you get its whole family for free!
Practice Time!
Master these verb conjugations from Lesson 15