Regular verbs in the present indicative have different conjugations in each verb group. Here are the regular conjugations of the third group [-ire].
| Person | -ire | Dormire | Verb [to sleep] |
| io tu lui/lei noi voi loro | -o -i -e -iamo -ite -ono | dorm-o dorm-i dorm-e dorm-iamo dorm-ite dorm-ono | I sleep you sleep he/she sleeps we sleep you sleep they sleep |
There are some particulate conjugations of verbs in the third conjugations such as.
1. Verbs in -isc.
Many verbs of the third conjugation -ire follow a different model of conjugation in the present indicative and add -isc before the first, second, and third person singular (io, tu, lui/lei) and the third person plural (loro):
| Person | -isc | Finire | Verb [to finish] |
| io tu lui/lei noi voi loro | –isco –isci –isce -iamo -ite –iscono | fin-isco fin–isci fin–isce fin-iamo fin-ite fin–iscono | I finish you finish he/she finishs we finish you finish they finish |
Here are some common verbs that follow this model:
| Capire (to understand) | Garantire (to guarantee) | Pulire (to clean) |
| Colpire (to hit) | Sostituire (to substitute) | Scolpire (to sculpt) |
| Costruire (to buid) | Spedire (to send) | Punire (to punish) |
| Custodire (to guard) | Unire (to unite) | Riferire (to report) |
| Fornire (to supply) | Riunire (to gather) | |
| Guarire (to heal) | Preferire (to prefer) |