This group of adverbs lets you confirm, deny, or hedge. Portuguese affirms with sim, claro, com certeza; denies with não; expresses doubt with talvez, quem sabe, provavelmente; and handles "me too / me neither" with também and its negative twin também não / tampouco. Two things will surprise English speakers: the emphatic post-verbal sim ("Eu fui sim!"), and the fact that some doubt adverbs force the subjunctive.
Affirmation: sim, claro, com certeza
Sim is the bare "yes." But Brazilians answer yes/no questions far more often by echoing the verb than by saying sim on its own — this is the single biggest difference from English.
— Você vem amanhã? — Venho.
— Are you coming tomorrow? — I am. (lit. 'I come' — echoing the verb instead of saying 'yes')
— Já almoçou? — Já.
— Have you eaten lunch? — Yes (already).
Other affirmations stack on emphasis: claro (of course), com certeza (definitely, for sure), certamente (certainly, more formal), realmente / de fato (indeed, really).
— Posso usar o banheiro? — Claro, fica ali no fundo.
— Can I use the bathroom? — Of course, it's in the back.
Com certeza vou na sua festa, não perco por nada.
I'll definitely come to your party, I wouldn't miss it for anything.
De fato, o trânsito hoje estava impossível.
Indeed, the traffic today was impossible. (formal/written register)
The emphatic post-verbal sim
Here is a construction with no English equivalent. To emphatically insist on something — especially when contradicting a doubt — Brazilians place sim right after the verb: "Eu fui sim!" It's roughly "I did go!" / "I sure did go!" The stress falls on the sim.
— Você não terminou o trabalho. — Terminei sim! Está aqui.
— You didn't finish the report. — I did so finish it! It's right here.
Eu te avisei sim, você é que não me ouviu.
I did warn you — you're the one who didn't listen.
English forces the emphasis onto a stressed auxiliary ("I did"). Portuguese has no "do-support," so it parks an emphatic sim after the verb instead. This sim is purely emphatic; the sentence is already complete without it.
Negation: não and friends
Não does double duty: it is both "no" (the answer) and "not" (the sentence negator). As a sentence negator it sits immediately before the verb complex.
— Você gostou? — Não, achei meio chato.
— Did you like it? — No, I found it kind of boring.
Eu não como carne de porco.
I don't eat pork.
To negate emphatically (the negative mirror of post-verbal sim), you can frame the verb: "Não fui não" = "I really didn't go." The doubled não is colloquial and extremely common in Brazil — the second não reinforces the first.
Não tô com fome não, obrigado.
I'm not hungry, really — thanks. (colloquial reinforcing não)
Other negative adverbs include nunca / jamais (never), nem (not even / nor), and tampouco (neither — formal). For the full machinery of double negation, see the negation pages.
também → também não / tampouco
Também means "also, too." Its negative counterpart is também não ("neither, not either") or, in formal register, tampouco. English uses two different words (too vs either); Portuguese just negates também.
| Situation | Portuguese | English |
|---|---|---|
| Agreeing with a positive | Eu também. | Me too. |
| Agreeing with a negative | Eu também não. / Nem eu. | Me neither. |
| Formal "neither" | tampouco | neither, nor (formal) |
— Adoro praia. — Eu também!
— I love the beach. — Me too!
— Não gosto de acordar cedo. — Nem eu.
— I don't like waking up early. — Me neither.
Ele não veio, e ela tampouco apareceu.
He didn't come, and she didn't show up either. (formal)
Doubt adverbs — and the subjunctive trap
Adverbs of doubt: talvez (maybe/perhaps), quem sabe (who knows / maybe), provavelmente (probably), possivelmente (possibly).
The critical point: talvez triggers the present subjunctive when it precedes the verb, because it marks the action as uncertain rather than factual. This is the same logic that drives the subjunctive everywhere — it's the mood of the not-yet-real.
Talvez ele venha mais tarde.
Maybe he'll come later. (venha = subjunctive of vir, not the indicative vem)
Talvez a gente vá para a praia no feriado.
Maybe we'll go to the beach over the holiday. (vá = subjunctive)
Quem sabe ela mude de ideia até lá.
Who knows, maybe she'll change her mind by then. (mude = subjunctive)
By contrast, provavelmente and possivelmente take the ordinary indicative, because "probably" still asserts the event as expected reality:
Provavelmente vou chegar atrasado.
I'll probably arrive late. (vou = indicative)
There's a nuance many learners miss: if talvez comes after the verb, the verb reverts to the indicative — "Ele vem talvez" (rare, colloquial). The subjunctive is tied to talvez standing before the verb. In practice, keep talvez up front and use the subjunctive.
Common Mistakes
❌ — Não gosto de café. — Eu também.
Incorrect — 'também' agrees with a positive; here it contradicts the speaker
✅ — Não gosto de café. — Eu também não.
— I don't like coffee. — Me neither.
❌ Talvez ele vem amanhã.
Incorrect — talvez requires the subjunctive (venha), not the indicative (vem)
✅ Talvez ele venha amanhã.
Maybe he'll come tomorrow.
❌ — Você terminou? — Sim, terminei sim sim.
Incorrect — one emphatic post-verbal sim is enough
✅ — Você terminou? — Terminei sim!
— Did you finish? — I sure did!
❌ Na verdade eu gostei muito! (meaning 'indeed, I really liked it')
Incorrect choice — 'na verdade' usually contradicts, not confirms
✅ De fato, gostei muito!
Indeed, I really liked it!
Key Takeaways
- Brazilians often answer yes by echoing the verb ("— Vem? — Venho") rather than saying sim.
- The emphatic post-verbal sim ("fui sim!") replaces English stressed-auxiliary "I did."
- Não = both "no" and "not"; colloquial doubled não ("não fui não") reinforces.
- "Me neither" = também não or nem eu — never plain também.
- Talvez before the verb forces the subjunctive (venha, vá, mude); provavelmente keeps the indicative.
Now practice Portuguese
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Portuguese →Related Topics
- Basic Negation with 'Não'A1 — How 'não' works as both 'no' and 'not', where it sits relative to the verb and clitics, how it behaves in compound tenses, and the friendly doubled 'não...não'.
- Adverbs: OverviewA2 — What adverbs are in Brazilian Portuguese, why they never agree, the main semantic types, and how -mente formation and flexible placement work.
- Talvez + SubjunctiveB1 — How 'talvez' (perhaps) triggers the subjunctive — and why its unusual position-sensitivity makes it different from every other subjunctive trigger in Brazilian Portuguese.
- Double Negation in BRA2 — Negative concord in Brazilian Portuguese: why 'não vi nada' is correct and required, when 'não' is obligatory, and the positional rule that makes it disappear.