Adverbial Clauses

An adverbial clause is a whole clause doing the job an adverb usually does: it tells you when, why, if, despite what, so that, so much that, or like what the main action happens. English does the same thing ("when she arrived", "because it's raining", "so that he could see"). The thing that catches English speakers off guard in Brazilian Portuguese is not the meaning of these clauses — it's that the conjunction itself decides whether the verb goes in the indicative or the subjunctive, and that talking about the future after certain time/condition words triggers a tense English doesn't even have: the future subjunctive.

This page sorts adverbial clauses by what they mean, gives you the conjunctions for each type, and — most importantly — tells you which mood each one demands and why.

The one idea that organizes everything: the conjunction picks the mood

Here is the underlying logic. The subjunctive in Portuguese marks an action that is not presented as an established fact — it lives in the world of the hypothetical, the not-yet-real, the merely-desired, or the irrelevant-to-truth. So:

• If the conjunction introduces something factual (a real time, a real cause), the verb stays in the indicative.
• If the conjunction inherently makes the action non-factual (a concession you grant, a purpose you aim at, an as-yet-unrealized condition), it forces the subjunctive.

Once you see why each conjunction leans one way, you stop memorizing lists and start predicting.

Temporal clauses (quando, enquanto, antes que/de, depois que/de, assim que)

Time clauses split cleanly. When the time reference is past or present (a real event), you use the indicative. When the reference is future (the event hasn't happened yet), quando, assim que, enquanto and depois que trigger the future subjunctive — this is the single most important thing on this page.

Same word, quando, but the second one is future, so the verb is chegar (future subjunctive of chegar), not chego. English uses plain present ("when I get home") here — Brazilians find this English habit strange, because to them the future is clearly future.

Antes que always takes the present subjunctive (the event is by definition not yet real); antes de + infinitive is the lighter everyday alternative. Depois que + indicative for past, future subjunctive for future; depois de + infinitive when the subject is the same.

Causal clauses (porque, já que, como, visto que)

Cause is the home of the indicative — a cause is, by definition, something real that you're treating as a fact. So porque, já que, como (meaning "since/as"), visto que and uma vez que all take the indicative.

Note the position: como in its causal sense almost always opens the sentence ("Como ninguém respondeu..."), while porque almost always follows the main clause. Putting porque at the front sounds wrong to native ears unless it's answering a "why?" question.

Conditional clauses (se, caso)

Se ("if") is the workhorse, and it follows the same future-subjunctive logic as time clauses: an open future condition takes the future subjunctive, not the present.

Caso means the same as se but is more (formal) and always takes the present subjunctive — there's no future-subjunctive version with caso.

For unreal/hypothetical conditions ("if I were rich..."), the imperfect subjunctive pairs with the conditional — that's covered in the conditional-sentences page.

Concessive clauses (embora, ainda que, mesmo que)

Concession is pure subjunctive territory, and the reason is beautiful: when you concede something, you're saying "grant this for the sake of argument — it doesn't change my point." You're explicitly not presenting it as decisive fact. So embora, ainda que, mesmo que and nem que all take the subjunctive.

In (informal) speech, Brazilians very often dodge embora entirely and just say mesmo / mesmo assim + indicative: "Tô cansado, mas vou terminar mesmo assim." That's worth recognizing, but in writing the subjunctive concessive is expected.

Purpose / final clauses (para que, a fim de que)

A purpose is a goal — not yet achieved, aimed at. Non-factual by nature, so subjunctive. Para que (everyday) and a fim de que (formal) take the subjunctive when the two clauses have different subjects.

When the subject is the same in both clauses, Brazilians strongly prefer para + infinitive instead — and this is one of the great workhorses of spoken BR: "Saí cedo para pegar o ônibus" ("I left early to catch the bus"), never "para que eu pegasse".

Consecutive (result) clauses (tão... que, tanto... que)

These express a result so extreme it produces a consequence: "so X that Y". The result actually happened, so the que-clause is indicative.

Comparative clauses (como, do que)

Comparisons of manner use como ("like/as"); comparisons of degree use mais/menos... do que. Both are factual → indicative.

Common Mistakes

This is the number-one English-speaker error: English uses the present after "when/if" for the future, so learners copy chego/quero. Brazilian Portuguese demands chegar/quiser.

English "because/so" overlap leads learners to mix cause (porque + indicative) with purpose (para que + subjunctive). Keep them apart: porque = real reason behind; para que = goal aimed at.

Key Takeaways

• The conjunction, not the verb, decides the mood. Factual time/cause/result/comparison → indicative. Concession, purpose, and caso/antes que conditions → subjunctive.
• Future reference after quando, se, assim que, enquanto, depois que triggers the future subjunctive — the single biggest break from English.
• When subjects match, BR swaps the subjunctive clause for an infinitive: para fazer, antes de sair, depois de comer. Use the full para que
  • subjunctive only when the subjects differ.