These six exceptions are ced/er, cess- sed/er, sess- mov/er, mot- ten/er, tent- vert/er, vers- veni/r, vent- and the verbs formed out of them using prefixes.
Estas seis excepcións son: ced/er, cess- sede/er, sess- mov/er, mot- ten/er, tent- vert/er, vers- veni/r, vent- e os verbos formados daquelas a forza de prefixos.