1. Essentials at a Glance

The fourth conjugation in Latin encompasses verbs whose present active infinitive ends in -īre, notably audīre (“to hear”) or venīre (“to come”). These verbs consistently feature a long -ī- on the present stem, making them relatively predictable compared to the sometimes irregular third conjugation. Mastering fourth conjugation forms—both regular and irregular—builds crucial confidence in Latin syntax, morphology, and reading comprehension, ensuring accurate interpretation of classical texts.

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2. Definition & Importance

Fourth conjugation verbs in Latin grammar are those typically ending in -īre (e.g., audīre, sentīre, servīre). They contribute a distinct set of Latin fourth conjugation examples that help differentiate patterns of tense and voice. Because many fourth conjugation verbs express core actions and states—like to hear (audīre) or to know (scīre)—they appear frequently in classical literature. Understanding them prevents common errors in Latin fourth conjugation and is essential for fluid reading, precise translation, and deeper insight into Latin rhetorical styles.

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3. Forms & Morphology

The fourth conjugation is recognized by its -ī- stem vowel and the infinitive ending -īre. Below is a simplified table of present indicative active endings, using audīre (“to hear”) as an example:

• Imperfect adds -ēbā- (e.g. audiēbam, “I was hearing”).
• Future uses forms like audiam, audiēs, audiet... mirroring third-conjugation futures.
• Perfect system typically adds -v- (e.g. audīvī, audīveram, audīverō).
• Irregular forms: Some verbs drop or alter the -v- (e.g., venīre → vēnī), so memorizing principal parts is key.

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4. Usage & Examples

Fourth conjugation verbs follow normal Latin syntax but often carry subtle idioms or extended senses:

1. Cicero, Pro Flacco 19:
   Mementote igitur… audire strepitum imperitorum.
   “Remember then… that you are hearing the clamor of inexperienced men.”

   audīre here implies not just hearing sounds but potentially paying heed to them.

2. Caesar, Commentarii de Bello Gallico:
   Prīmam aciem in armīs esse, tertiam castra mūnīre iussit.
   “He ordered the third line to fortify the camp.”

   mūnīre (to fortify) underscores Caesar’s military clarity.

3. Vergil, Aeneid IV.11:
   Iliacosque iterum dēmēns audīre labōrēs exposcit…
   “Madly, she again demands to hear the Trojan struggles…”

   audīre stands at the heart of Dido’s longing to listen to Aeneas’s tale.

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5. Common Pitfalls

• Confusing with Third -io Verbs: Verbs like capio, capere (3rd) can look similar to servio, servīre (4th). Always check the infinitive ending.
• Irregular Perfects: Certain fourth conjugation verbs (e.g., venīre → vēnī, sentīre → sēnsī) deviate from the -vī pattern.
• Deponent Usage: Verbs like potīrī have passive forms but active meanings; potior often takes the ablative (potior rēgnō).
• Idiomatic Meanings: audīre can mean “obey,” and male audīre can mean “to be spoken ill of.”

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6. Additional Notes & Nuances

Although the -īre ending is typically straightforward, certain historical and phonetic shifts produce exceptions (e.g., aperīre → aperuī). Deponent fourth-conjugation verbs, such as orīrī (to rise) or mentīrī (to lie), maintain passive endings with active meanings. Moreover, usage extends beyond literal sense: nesciō an frequently means “perhaps,” and bene audīre implies a good reputation rather than simply hearing well. Advanced learners should track these nuances to appreciate an author’s subtleties fully.

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7. Key Takeaways

• The infinitive in -īre (long ī) is the hallmark of Latin’s fourth conjugation.
• Conjugations show mostly regular patterns, yet memorize irregular perfect stems (vēnī, sēnsī).
• Fourth conjugation shares future and subjunctive endings with third conjugation (-am, -ēs, -et, etc.).
• Context clarifies when forms like audiam function as future indicative or present subjunctive.
• Idiomatic expressions (male audīre, potīrī rēgnō) demand careful note for accurate translation.