Mentir means to lie — to deliberately say something untrue. It belongs to the family of e→i stem-changing -ir verbs, the same group as sentir, preferir, vestir and servir. The trap is the first-person singular: it's minto, not "*mento." Brazilians use this verb constantly in conversation ("Não minto pra você, juro!"), so the irregular form comes up the moment you start defending your honesty.
Why "minto" and not "mento"
In a small set of -ir verbs, the stem vowel e rises to i whenever the verb is stressed on that vowel and the ending begins with a back vowel (o or a). That happens in exactly two places:
- First-person singular present: minto.
- The entire present subjunctive: minta, mintas, minta, mintamos, mintam.
Everywhere else — mente, mentimos, mentem, and the whole past system — the e stays put, because either the stress falls elsewhere or the ending starts with e or i.
This is a vocalic change (e→i), unlike the consonantal d→ç of medir or pedir. Keeping the two patterns straight is what separates an intermediate learner from a polished one: you'll never write "*minço" or "*medo" once you know which verb does which.
Present indicative (presente do indicativo)
Only the first person changes.
| Pronoun | Form |
|---|---|
| eu | minto |
| tu/você | mente |
| ele/ela | mente |
| nós | mentimos |
| vocês | mentem |
| eles/elas | mentem |
Eu não minto pra você, juro que foi sem querer.
I'm not lying to you, I swear it was an accident.
Ela mente descaradamente e ainda fica ofendida quando a gente desconfia.
She lies brazenly and still gets offended when we doubt her.
Vocês mentem tão mal que dá pra perceber na hora.
You guys lie so badly that you can tell right away.
Preterite (pretérito perfeito) — fully regular
No stem change anywhere in the past.
| Pronoun | Form |
|---|---|
| eu | menti |
| tu/você | mentiu |
| ele/ela | mentiu |
| nós | mentimos |
| vocês | mentiram |
| eles/elas | mentiram |
Ele mentiu sobre a idade no aplicativo de namoro.
He lied about his age on the dating app.
Eu menti uma vez na vida e me arrependo até hoje.
I lied once in my life and I regret it to this day.
Imperfect (pretérito imperfeito) — regular
| Pronoun | Form |
|---|---|
| eu | mentia |
| tu/você | mentia |
| ele/ela | mentia |
| nós | mentíamos |
| vocês | mentiam |
| eles/elas | mentiam |
Quando criança, eu mentia que tinha feito a lição.
As a kid, I used to lie that I'd done my homework.
Future and conditional — regular
| Pronoun | Futuro do presente | Futuro do pretérito (conditional) |
|---|---|---|
| eu | mentirei | mentiria |
| tu/você | mentirá | mentiria |
| ele/ela | mentirá | mentiria |
| nós | mentiremos | mentiríamos |
| vocês | mentirão | mentiriam |
| eles/elas | mentirão | mentiriam |
Eu nunca mentiria sobre uma coisa dessas.
I would never lie about something like that.
Colloquially, vou mentir replaces mentirei in almost all speech.
Subjunctive — where the i returns
The present subjunctive is built on the minto stem, so the i spreads across the paradigm: minta, mintas, minta, mintamos, mintam. The imperfect and future subjunctive use the regular preterite stem menti-, so the e stays.
| Pronoun | Presente do subjuntivo | Imperfeito do subjuntivo | Futuro do subjuntivo |
|---|---|---|---|
| eu | minta | mentisse | mentir |
| tu/você | minta | mentisse | mentir |
| ele/ela | minta | mentisse | mentir |
| nós | mintamos | mentíssemos | mentirmos |
| vocês | mintam | mentissem | mentirem |
| eles/elas | mintam | mentissem | mentirem |
Não quero que você minta pra mim, prefiro a verdade doída.
I don't want you to lie to me; I'd rather have the painful truth.
Se ele mentir de novo, acabou a confiança.
If he lies again, the trust is gone.
Imperative
| Pronoun | Affirmative | Negative |
|---|---|---|
| tu | mente | não mintas |
| você | minta | não minta |
| nós | mintamos | não mintamos |
| vocês | mintam | não mintam |
The most common real-life form is the negative: Não minta pra mim! (Don't lie to me!).
Não minta pra sua mãe, ela sempre descobre.
Don't lie to your mother — she always finds out.
Non-finite forms
| Form | Value |
|---|---|
| Infinitivo | mentir |
| Infinitivo pessoal (nós) | mentirmos |
| Infinitivo pessoal (vocês/eles) | mentirem |
| Gerúndio | mentindo |
| Particípio | mentido |
Meaning and prepositions
- mentir para alguém — to lie to someone. This is the standard pattern in Brazil. In speech, para contracts colloquially to pra: "Ele mentiu pra mim."
- mentir sobre algo — to lie about something: "mentiu sobre o salário."
- The agent noun is mentiroso/mentirosa (liar), and the lie itself is a mentira. The verb is mentir; do not confuse it with mencionar (to mention) — a tempting false friend for English speakers, since English has no "*to ment."
Common Mistakes
❌ Eu mento muito mal.
Incorrect — the 1sg is 'minto', with i.
✅ Eu minto muito mal.
I'm a terrible liar (lit. I lie very badly).
❌ Não quero que você menta.
Incorrect — present subjunctive is 'minta', not 'menta'.
✅ Não quero que você minta.
I don't want you to lie.
❌ Ele mentiu a mim.
Incorrect — mentir takes 'para/pra', not 'a' for the person, in everyday BR.
✅ Ele mentiu pra mim.
He lied to me.
❌ Você me mentiu sobre isso.
Incorrect — no direct-object 'me'; the person is the indirect object with para.
✅ Você mentiu pra mim sobre isso.
You lied to me about this.
Lock in the pair: minto (present, 1sg) and minta (present subjunctive). Everywhere else, the e holds.
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Start learning Portuguese→Related Topics
- Stem-Changing -ir VerbsA2 — The predictable e→i and o→u vowel shift in the eu form of many Brazilian Portuguese -ir verbs, and why it reappears throughout the subjunctive.
- Summary of Irregular Present Indicative FormsA2 — A consolidated reference table of the most common irregular Brazilian Portuguese verbs in the present indicative, grouped by the type of irregularity — suppletive stems, -g-/-ç- eu forms, -z- stems, and vowel-changing -ir verbs.
- SentirA1 — How to conjugate and use sentir (to feel, to sense, to be sorry) in Brazilian Portuguese — an -ir verb with the e→i stem change in the eu form (sinto) and throughout the present subjunctive.
- PreferirA1 — The stem-changing -ir verb 'preferir' (to prefer), with the e→i change in prefiro and the present subjunctive prefira, plus the crucial 'preferir A' construction ('prefiro chá a café') instead of the wrong 'do que'.
- Stem-Changing Verbs OverviewA2 — How and why the stem vowel shifts in certain Brazilian Portuguese verbs — and how that differs from purely spelling changes.