The Three Conjugation Classes: -are, -ere, -ire

Every Italian verb belongs to one of three families, defined by the ending of the infinitive: -are, -ere, or -ire. These families — the prima, seconda, and terza coniugazione — share most of their grammar but differ in their endings, in their behaviour under irregularity, and (for the third class) in whether they take the infamous -isc- infix in the present tense. Knowing which family a verb belongs to is the first thing you do when you sit down to conjugate it.

Prima coniugazione: -are verbs

The first conjugation is by far the largest. Estimates put it at around 65% of all Italian verbs, and the proportion grows year by year because -are is the only fully productive class — virtually every new verb that enters Italian joins it. When you see a noun get verbed (messaggio → messaggiare) or an English borrowing get integrated (to chat → chattare, to click → cliccare, to scroll → scrollare), the result will end in -are.

This class also contains many of the most common everyday verbs:

A sample present-tense conjugation: parlare

To conjugate a regular -are verb in the present indicative, drop -are to find the stem (parl-) and add the endings: -o, -i, -a, -iamo, -ate, -ano.

For full coverage of this class in the present, see Regular -are Verbs.

Seconda coniugazione: -ere verbs

The second conjugation is smaller — perhaps 20–25% of the lexicon — and it has a much higher concentration of irregular verbs. Many of Italian's most essential verbs live here, including a long list of -ere verbs whose past participles do not follow the regular pattern.

Stem stress: prèndere vs vedére

Italian -ere verbs split into two stress patterns at the infinitive. Most are stem-stressed — the accent falls on the syllable before -ere: prèndere, scrìvere, lèggere, chiùdere, crèdere. A smaller group is ending-stressed: vedére, sapére, avére, dovére, temére, cadére. The dictionary form does not write the accent, so you have to learn it from listening.

This stress difference matters only at the infinitive. Once you start conjugating, the pattern follows the regular endings and the stress shifts to wherever the conjugation puts it.

A sample present-tense conjugation: prendere

Drop -ere to find the stem (prend-) and add: -o, -i, -e, -iamo, -ete, -ono.

Notice how similar this is to parlare — the only differences are -e (not -a) for the third person singular, -ete (not -ate) for the voi form, and -ono (not -ano) for loro. See Regular -ere Verbs for more.

Terza coniugazione: -ire verbs

The third conjugation is the smallest and the trickiest — not because the conjugation itself is hard, but because the class splits into two subgroups that look identical at the infinitive and behave differently in the present tense.

The "pure" subgroup

These -ire verbs conjugate with the regular endings: -o, -i, -e, -iamo, -ite, -ono. They include some of the most basic verbs in the language.

A sample conjugation: dormire

Drop -ire to find dorm- and add: -o, -i, -e, -iamo, -ite, -ono.

The -isco subgroup

The other (and larger) group of -ire verbs inserts -isc- between the stem and the ending in four out of six present-tense forms — every form except noi and voi. There is no logical rule for which verbs do this; you must learn it for each verb. The signature member of this subgroup is finire (to finish):

Notice the alternation: finisco, finisci, finisce in the singular, then back to finiamo, finite in the noi and voi forms, then finiscono again for loro. The -isc- shows up wherever the stress falls on the stem; it disappears in noi and voi, where the stress shifts to the ending.

Common -isco verbs include:

For the deep dive on this subgroup, see Regular -ire Verbs (-isco subgroup). For the pure subgroup, see Regular -ire Verbs.

Putting them side by side

Here are all three classes in the present indicative, lined up so the patterns jump out:

Three observations worth carrying with you. First, the io form ends in -o in all three classes. Second, the noi form ends in -iamo in all three classes. Those two endings are stable across the entire system. Third, the only place where -ere and -ire pure verbs differ in the present is the voi form: prendete vs dormite. Otherwise they share the -o, -i, -e, -iamo, …, -ono endings.

How to tell which subgroup an -ire verb belongs to

There is no spelling rule. You learn each -ire verb with its subgroup the way you learn vocabulary. As a rough heuristic, the most basic -ire verbs (dormire, sentire, partire, aprire, offrire, seguire, servire) tend to be pure, while verbs derived from nouns or adjectives or with abstract meanings (finire, capire, preferire, pulire, costruire) tend to take -isc-. But there are exceptions on both sides, so when you meet a new -ire verb, look it up.

A handful of verbs allow both forms with no real difference in meaning: applaudire gives both applaudo and applaudisco; mentire gives both mento and mentisco. Modern usage tends to prefer the -isc- version for these dual-membership verbs.

Common mistakes

Where to go next

Once you can spot a verb's class on sight, move into the present indicative pages for each one: Regular -are Verbs, Regular -ere Verbs, Regular -ire Verbs, and the all-important Regular -ire Verbs (-isco subgroup). The patterns you learn here recur in every other tense — the endings change, but the three-class architecture stays the same.