Verbs Ending in -iar

Verbs whose infinitive ends in -iar look deceptively uniform. In fact, the class splits into two sharply different paradigms, and the split does not announce itself in the infinitive — you have to learn which verbs belong to which group. The overwhelming majority of -iar verbs are fully regular -ar verbs: the stem i just sits there, unchanged, through the whole paradigm, and you write confio, confias, confia, confiamos, confiam with no tricks at all. A small, closed set of six verbs — easy to memorize with the mnemonic MARIO + Premiar — does something quite different: it inserts an e before the stem i whenever the stem is stressed, producing diphthong forms like medeio, anseio, odeio. Learning the mnemonic is the whole battle. Once you know which verbs are in the MARIO group, everything else in the class is automatic.

The two patterns at a glance

The difference only surfaces in the stressed-stem forms of the present indicative and present subjunctive — the four "boot" forms where the eu, tu, ele and eles endings pull stress onto the stem vowel. In the nós form, stress shifts to the ending, and both paradigms converge on the same spelling.

The surface difference is a single inserted e, but it reflects a real pronunciation difference. In copio, the stressed syllable is CO, and the -io is a falling semivowel: /ˈkɔ.pju/. In odeio, the stressed syllable is -dei-, containing an open-e diphthong: /uˈdɐj.u/. Portuguese orthography is recording what the tongue actually does.

Pattern A: regular -iar verbs

The default -iar verb is fully regular. The i of the stem is invariant, and the endings are exactly those of any regular -ar verb. There are no traps — the only thing to watch is that the 1sg, 3sg and 3pl sound like a tight diphthong, which learners sometimes want to break up by inserting an e they have seen in MARIO verbs. Resist the temptation.

Copiar (to copy) — full present indicative and subjunctive

Confiar (to trust)

Confiar takes the preposition em (confiar em alguém, confiar em algo) — not de or nothing, as English speakers sometimes assume.

Enviar (to send)

A broader list of regular -iar verbs

Pattern B: the MARIO + Premiar group

Six verbs — and only these six — insert an e between the stem and the ending whenever the stem is stressed. The result is a form spelled -ei- in the boot, exactly as in the -ear verb class. In the nós form, the stress shifts to the ending, the inserted e disappears, and the verb looks regular again.

The mnemonic:

• Mediar — to mediate
• Ansiar — to yearn, long for
• Remediar — to remedy
• Incendiar — to set on fire
• Odiar — to hate
• Plus Premiar — to award, give a prize

Some grammars call this the ANIMADO set or the MARIO-IC set. Whatever label you prefer, the membership is the same six verbs.

Odiar (to hate) — full paradigm

Mediar (to mediate)

Ansiar (to yearn, long for)

Ansiar takes the preposition por (ansiar por algo) — "to yearn for something." In more formal registers you may see ansiar de or direct object construction, but ansiar por is the standard modern usage.

Remediar (to remedy, fix)

Incendiar (to set on fire)

Premiar (to award, give a prize to)

A side-by-side sanity check

A useful drill is to write the 1sg present of several -iar verbs and check whether they look like copio or like odeio:

Only the six MARIO verbs take the diphthong. Everything else keeps the plain -iar stem.

Preterite and the nós acute accent

In the preterite, both patterns converge: the -iar verb is a plain -ar verb and inserts no vowel. However, in European Portuguese the 1pl preterite carries an acute accent to distinguish it from the present — this is one of the most visible PT-PT spellings and survives the 1990 Orthographic Accord intact (Brazilian Portuguese drops it).

Note: both confiámos and odiámos carry the acute accent on the á. The accent is the difference between present (confiamos — we trust) and preterite (confiámos — we trusted). Dropping it changes the tense.

Imperfect, future, and conditional

All fully regular -ar paradigms, with no inserted vowel and no acute accent in the 1pl.

• Imperfect: copiava, copiavas, copiava, copiávamos, copiavam / odiava, odiavas, odiava, odiávamos, odiavam.
• Future: copiarei, copiarás, copiará, copiaremos, copiarão / odiarei, odiarás, odiará, odiaremos, odiarão.
• Conditional: copiaria, copiarias, copiaria, copiaríamos, copiariam / odiaria, odiarias, odiaria, odiaríamos, odiariam.

Past participle and gerund

Both are regular. Past participle: copiado, confiado, enviado, odiado, mediado, anseado (sic — careful: ansiado, not anseado). The inserted e of the MARIO group does not propagate to non-finite forms. Gerund: copiando, confiando, enviando, odiando, mediando, ansiando.

Spanish comparison

Spanish has a parallel split in its -iar verbs, but the membership is different, and the Spanish MARIO list is much shorter — essentially just verbs of the -iar class like enviar and variar that take an accent on the í (envío, varío) rather than inserting an e. Portuguese does not accent the i; it inserts an e instead. The key equivalences:

In particular, Portuguese never writes an accent on the stem i the way Spanish writes envío, confío. If a Portuguese -iar verb would "need" an accent by Spanish logic, drop the accent and leave the i plain.

English comparison

English has no moving stress in its verb paradigm and no stem-vowel insertion. The closest thing to this kind of orthographic-phonological dance is the alternation of electric / electricity or photograph / photography, where stress shift changes the vowel quality — but this is in word-formation, not in verb conjugation. English speakers need to accept that Portuguese spelling follows pronunciation very faithfully, and a shifting stress is spelled out in the vowels on the page.

Common Mistakes

The MARIO verbs always insert an e before the stem i in the boot forms. Odio (without the e) would be the form of a non-existent regular verb.

The MARIO pattern only applies to stressed-stem forms. Nós always shifts stress to the ending, so odiamos, mediamos, anseamos — wait, that one is a trap: ansiamos (not anseamos). The inserted e drops whenever stress moves off the stem.

Overgeneralizing the MARIO pattern to all -iar verbs is the most frequent error in this class. Memorize the six; everything else is confio, copio, envio, inicio, vario.

Spanish-speakers often import the envío accent. Portuguese leaves the i unaccented in the present.

In European Portuguese, the 1pl preterite of -ar verbs takes an acute accent on the á (confiámos, copiámos, odiámos). Without the accent, the form reads as the present tense. Brazilian Portuguese drops the accent, but PT-PT keeps it — and in the 1990 Orthographic Accord this distinction was preserved.

Key takeaways

• The -iar class divides into two sharp sub-patterns, and membership is fixed by the verb, not predictable from the infinitive.
• Pattern A (regular) covers the vast majority: confio, copio, envio, inicio, anuncio, vario, crio. Treat as a normal -ar verb with -i- in the stem.
• Pattern B (MARIO + Premiar) covers exactly six verbs: mediar, ansiar, remediar, incendiar, odiar, and premiar. Stressed-stem forms insert an e and become medeio, anseio, remedeio, incendeio, odeio, premeio. The inserted e disappears in the nós form.
• The acute accent on the 1pl preterite (confiámos, odiámos) is standard European Portuguese spelling and survives the 1990 Orthographic Accord.
• Never accent the stem i (don't write envío — that is Spanish). Portuguese marks stress differently.