> This group of verbs—which originated in the Latin inchoative verbs but now includes other verbs as well— substitute -zc- for stem-final -c- before o and a. The group includes nearly all verbs ending in -acer (except hacer and derived verbs), -ecer (except mecer and remecer), -ocer (except cocer and derived verbs), and -ucir. For example:
nacer: yo nazco, tú naces...
crecer: yo crezco, tú creces...
conocer: yo conozco, tú conoces...
producir: yo produzco, tú produces...
Yacer may alternatively be conjugated with -zc- (yazco), -g- (yago) or a compromise -zg- (yazgo).