The verbs in the fourth conjugation have second principal parts that end in -īre.
The present passive infinitive form of fourth conjugation verbs end in -īrī.
audiō, audīre, audīvī, audītus (to hear)
present passive infinitive: audīrī (to be heard)
| (Active) | Present | Imperfect | Future | Perfect | Pluperfect | Future Perfect | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sing. 1st | audiō | audiēbam | audiam | audīvī | audīveram | audīverō | ||||||
| Sing. 2nd | audīs | audiēbās | audiēs | audīvistī | audīverās | audīveris | ||||||
| Sing. 3rd | audit | audiēbat | audiet | audīvit | audīverat | audīverit | ||||||
| Plu. 1st | audīmus | audiēbāmus | audiēmus | audīvimus | audīverāmus | audīverimus | ||||||
| Plu. 2nd | audītis | audiēbātis | audiētis | audīvistis | audīverātis | audīveritis | ||||||
| Plu. 3rd | audiunt | audiēbant | audient | audīvērunt | audīverant | audīverint |
| (Passive) | Present | Imperfect | Future | |||
|---|---|---|---|---|---|---|
| Sing. 1st | audior | audiēbar | audiar | |||
| Sing. 2nd | audīris | audiēbāris | audiēris | |||
| Sing. 3rd | audītur | audiēbātur | audiētur | |||
| Plu. 1st | audīmur | audiēbāmur | audiēmur | |||
| Plu. 2nd | audīminī | audiēbāminī | audiēminī | |||
| Plu. 3rd | audiuntur | audiēbantur | audientur |