La e changes to ie in all the singular persons and in the third person of the plural of the present indicative and in the whole present subjunctive.
- E AR acertar, acrecentar, alentar, apretar, arrendar, asentar, asosegar, aterrar, atravesar, calentar, cegar, cerrar, comenzar, concertar, confesar, denegar, desalentar, desasosegar, desconcertar, desenterrar, deshelar, desmembrar, despertar, desplegar, desterrar, emparentar, empezar, encerrar, encomendar, enmendar, ensangrentar, enterrar, errar, escarmentar, fregar, gobernar, helar, herrar, invernar, manifestar, mentar, merendar, negar, nevar, pensar, plegar, quebrar, recalentar, recomendar, refregar, regar, remendar, renegar, repensarse, replegar, restregar, reventar, salpimentar, segar, sembrar, sentar, serrar, sosegar, soterrar, subarrendar, temblar, tentar, tropezar.
- E ER ascender, atender, defender, desatender, descender, encender, entender, extender, heder, perder, sobrentender, tender, trascender, verter.
- E IR cernir, concernir * , discernir.
| Present indicative | Present subjunctive | Imperative |
| Yo pienso | Yo piense | |
| Tú piensas | Tú pienses | Tú piensa |
| Él piensa | Él piense | Usted piense |
| Nosotros pensamos | Nosotros pensemos | Nosotros pensemos |
| Vosotros pensáis | Vosotros penséis | Vosotros pensad |
| Ellos piensan | Ellos piensen | Ustedes piensen |
* Concernir is defective. It is used in third persons of the present indicative, the present subjunctive, the imperfect indicative and the imperfect subjunctive, in the past and present participles, and in gerund.