This is a regular verb. It follows the conjugation pattern of the verb hablar.
Present:
Ceno temprano entre semana.
I have dinner early on weekdays.
Preterite:
Anoche cenamos en un restaurante nuevo.
Last night we had dinner at a new restaurant.
Negative Imperative:
No cenen pesado justo antes de dormir.
Don't have a heavy dinner right before going to bed.