Several verbs ending in -rir (abrir, cubrir and their derivatives except for desabrir) follow the regular conjugation pattern of verbs in -ir with one exception: their past participle ends in -ierto (instead of -ido): cubrir / cubierto, abrir / abierto
8 verbs follow this model. Below an extract:
To see other models, refer to Model Table
Based on the ending, you can identify features that different verbs have in common. Click on the verbs above to see their conjugation tables and explore their conjugation patterns.