The imperfect subjunctive is the engine of hypothetical Portuguese. Anytime you talk about something that is contrary to fact, wished for, or filtered through a past-tense feeling, this is the form that does the work. Brazilians reach for it constantly and casually — so unlike in some languages, where the imperfect subjunctive can sound bookish, in Brazilian Portuguese it is everyday speech. This page drills its four core uses so you can both recognize and produce them naturally.
Use 1: hypothetical "se" clauses
This is the workhorse. When you set up a condition that is contrary to fact or merely imagined — "if I had," "if I were," "if I could" — the se clause takes the imperfect subjunctive. The result clause then takes the conditional (formal) or the colloquial imperfeito (informal).
Se eu tivesse dinheiro, eu compraria uma casa.
If I had money, I'd buy a house. (formal result)
Se eu fosse você, eu não faria isso.
If I were you, I wouldn't do that.
Se ela soubesse a verdade, ficaria muito brava.
If she knew the truth, she'd be very angry.
A crucial point for English speakers: the imperfect subjunctive here is not about past time. Se eu pudesse, eu ajudaria means "If I could, I'd help" — about the present or general situations, not the past. The "past-looking" morphology signals distance from reality, exactly as English "If I were" uses a past-looking form for a present hypothetical.
Se eu pudesse, eu te ajudaria agora mesmo.
If I could, I'd help you right now.
Use 2: past-tense triggers of will, emotion, and doubt
The present subjunctive follows triggers in the present (Quero que ele venha). When that trigger is in the past — the main verb is in the preterite, imperfect, or conditional — the subordinate verb shifts to the imperfect subjunctive. This is the "sequence of tenses" rule, and it is automatic.
Eu queria que ele viesse à festa.
I wanted him to come to the party.
Era importante que ela falasse com o chefe.
It was important that she speak with the boss.
A gente duvidava que aquilo desse certo.
We doubted that would work out.
Compare the two timeframes side by side. The trigger's tense drags the subjunctive along with it.
| Trigger in present → present subjunctive | Trigger in past → imperfect subjunctive |
|---|---|
| Quero que ele venha. (I want him to come.) | Eu queria que ele viesse. (I wanted him to come.) |
| É importante que ela fale. (It's important she speak.) | Era importante que ela falasse. (It was important she speak.) |
| Duvido que dê certo. (I doubt it'll work.) | Duvidava que desse certo. (I doubted it'd work.) |
Use 3: como se (as if)
Como se — "as if" / "as though" — introduces an explicitly unreal comparison, so it always takes the imperfect subjunctive (or the past perfect subjunctive for earlier events). This is true even when the main clause is in the present, because the comparison itself is counterfactual.
Ele fala como se soubesse tudo.
He talks as if he knew everything.
Ela me tratou como se eu fosse um estranho.
She treated me as if I were a stranger.
O cachorro olhava para mim como se entendesse cada palavra.
The dog looked at me as if it understood every word.
Note the contrast with English: English allows "as if he knows everything" (indicative) in casual speech, but Portuguese como se locks in the subjunctive every time. There is no "como se sabe tudo."
Use 4: softened wishes and "quem dera"
The imperfect subjunctive carries wishes that you know are unlikely or impossible — the "if only" feeling. The classic frame is quem dera ("if only" / "I wish"), an idiom so common that learners should treat it as a fixed expression.
Quem dera eu tivesse mais tempo!
If only I had more time!
Tomara que dê tudo certo — ah, quem dera fosse tão fácil.
Hope it all works out — ah, if only it were that easy.
You will also hear oxalá (more literary) and the simple eu queria que... doing the same job.
Eu queria tanto que você estivesse aqui comigo.
I so wish you were here with me.
Why Brazilians use it so freely
In some languages the imperfect subjunctive feels formal or even archaic in everyday talk. Not in Brazilian Portuguese. Se eu fosse, se eu tivesse, se eu pudesse are bread-and-butter conversation, used by everyone regardless of education or region. What does shift by register is the result clause — formal speech and writing use the conditional (compraria), while casual speech swaps in the imperfeito indicative (comprava) or ia comprar. The se clause's imperfect subjunctive stays constant across all registers. So you can rely on this form heavily without ever sounding stiff.
Common Mistakes
❌ Se eu tinha dinheiro, eu comprava uma casa.
Incorrect — 'tinha' is imperfect indicative; the hypothetical 'se' needs the subjunctive.
✅ Se eu tivesse dinheiro, eu comprava uma casa.
If I had money, I'd buy a house.
This is the number-one transfer error. English "if I had" looks like a plain past, so learners use tinha. Portuguese demands the imperfect subjunctive tivesse in the condition.
❌ Eu queria que ele vem à festa.
Incorrect — present indicative after a past trigger; needs the imperfect subjunctive.
✅ Eu queria que ele viesse à festa.
I wanted him to come to the party.
❌ Ele fala como se sabe tudo.
Incorrect — 'como se' always takes the subjunctive, never the indicative.
✅ Ele fala como se soubesse tudo.
He talks as if he knew everything.
❌ Se eu seria você, eu não faria isso.
Incorrect — the conditional 'seria' can't go in the 'se' clause.
✅ Se eu fosse você, eu não faria isso.
If I were you, I wouldn't do that.
English "If I would be" tempts learners to put a conditional in the se clause. In Portuguese the condition is the imperfect subjunctive (fosse); only the result clause gets the conditional.
❌ Quem dera eu tenho mais tempo!
Incorrect — 'quem dera' requires the imperfect subjunctive.
✅ Quem dera eu tivesse mais tempo!
If only I had more time!
Key Takeaways
- Use the imperfect subjunctive in hypothetical se clauses (se eu tivesse), even for present-time hypotheticals — it marks unreality, not past time.
- A past-tense trigger of will/emotion/doubt pulls the subjunctive into the imperfect (eu queria que ele viesse).
- como se ("as if") always takes it: como se soubesse tudo.
- Use it for wishes, especially after quem dera ("if only").
- It is fully colloquial in Brazil — using it does not make you sound formal.
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Start learning Portuguese→Related Topics
- Imperfeito do Subjuntivo: FormationB1 — How to build the imperfect subjunctive in Brazilian Portuguese — the single most predictable irregular form, derived directly from the third-person plural preterite.
- Contrary-to-Fact Conditionals (Present)B1 — Present hypotheticals in Brazilian Portuguese — se + imperfect subjunctive + conditional (Se eu tivesse dinheiro, compraria), and the colloquial swap of conditional for imperfect indicative (comprava).
- Imperfeito in Counterfactual and Hypothetical ContextsB1 — How Brazilian Portuguese uses the imperfeito as a colloquial stand-in for the conditional in hypotheticals, wishes, and contrary-to-fact sentences.
- Conditional for Hypothetical SituationsB1 — Using the conditional in 'if...would' sentences, plus the colloquial Brazilian habit of replacing it with the imperfect indicative.
- Sequence of Tenses with SubjunctiveB2 — How the tense of the main verb decides which subjunctive tense follows — the predictable matching rule that lets you choose 'venha', 'viesse', or 'tenha vindo' automatically.