A compound sentence (frase composta por coordenação) is built from two or more independent clauses joined by a coordinating conjunction. Each clause could stand alone as its own sentence — they are grammatical equals, linked side by side rather than one being grammatically dependent on the other. This is the structural step up from a simple sentence, and the contrast matters: compound sentences let you stack facts, balance contrasts, and give alternatives, all while keeping each idea on equal footing.
What makes a sentence compound
The defining property: both halves are complete clauses on their own. Break the conjunction, and you get two sentences that could each stand alone.
Ela canta e ele toca guitarra.
She sings and he plays guitar.
This compound sentence is built from two independent clauses: Ela canta and Ele toca guitarra. Either could stand alone. The conjunction e joins them as grammatical equals.
Contrast this with a complex sentence (covered on its own page), where one clause is grammatically subordinate to the other:
Ela canta quando ele toca guitarra.
She sings when he plays guitar.
Here quando ele toca guitarra cannot stand alone — it needs the main clause Ela canta to anchor it. That is subordination, not coordination. Compound sentences only use coordination.
The main coordinating conjunctions
Portuguese has a small, high-frequency inventory of coordinators. Each one expresses a specific logical relationship between the two clauses: addition, contrast, alternative, or consequence.
| Conjunction | Type | Meaning |
|---|---|---|
| e | additive | and |
| nem | additive (negative) | nor, and not |
| mas | adversative | but |
| porém | adversative (formal) | however |
| contudo | adversative (formal) | however, nonetheless |
| todavia | adversative (formal) | nevertheless |
| ou | alternative | or |
| ou... ou | alternative (correlative) | either... or |
| pois | explanatory / consequential | for, since, so |
| portanto | consequential | therefore, so |
| logo | consequential | so, therefore |
| assim | consequential | thus, so |
Additive coordination: e and nem
The workhorse of Portuguese coordination is e. It stacks facts, actions, or descriptions without changing their logical relationship — simple addition.
A Marta estuda medicina e o irmão estuda direito.
Marta studies medicine and her brother studies law.
Acordei cedo, tomei o pequeno-almoço e fui trabalhar.
I woke up early, had breakfast, and went to work.
When both clauses are negative, Portuguese uses nem — the negative counterpart of e.
Não fumo nem bebo.
I don't smoke and I don't drink.
Ela não ligou nem apareceu.
She didn't call and didn't show up.
Nem can also be the first conjunction in a correlative pair: nem... nem (neither... nor).
Nem o João nem a Ana querem ir.
Neither João nor Ana wants to go.
Nem chove nem faz sol — que tempo estranho.
It neither rains nor shines — what strange weather.
Adversative coordination: mas, porém, contudo, todavia
Adversative conjunctions signal contrast or opposition. Mas is by far the most common and works at any register.
Estou cansado, mas vou trabalhar.
I'm tired, but I'm going to work.
Gosto do Porto, mas prefiro Lisboa.
I like Porto, but I prefer Lisbon.
Tentei ligar-lhe, mas não atendeu.
I tried to call him, but he didn't answer.
Porém, contudo, todavia are all roughly equivalent to English however / nevertheless — formal, typical of writing, opinion columns, and careful speech. Unlike mas, they can move around the clause and are often set off by commas.
O plano parecia bom; porém, falhou.
The plan seemed good; however, it failed.
Os dados são preliminares; contudo, apontam para uma tendência clara.
The data are preliminary; however, they point to a clear trend.
Ele prometeu ajudar; todavia, nunca apareceu.
He promised to help; nevertheless, he never showed up.
Alternative coordination: ou
Ou presents alternatives — the listener should pick one, or the speaker genuinely does not know which is true.
Tens tempo agora ou queres falar mais tarde?
Do you have time now or do you want to talk later?
Podemos ir de carro ou apanhar o comboio.
We can drive or take the train.
Ela está no escritório ou já foi para casa.
She's at the office or has already gone home.
For emphatic alternatives — either... or — Portuguese doubles up: ou... ou.
Ou ficas em casa ou vais com os outros.
Either you stay home or you go with the others.
Ou ele paga a conta ou não voltamos cá.
Either he pays the bill or we're not coming back here.
This correlative pattern adds force, ruling out a middle ground.
Explanatory and consequential coordination: pois, portanto, logo, assim
Portuguese has several coordinators that express cause or consequence at the same coordinate level — neither clause is subordinate, but the second clause draws a conclusion from the first.
Pois at the start of the second clause means for or since, offering the reason for what was just stated. This is the coordinating use — not to be confused with the high-frequency pragmatic pois (covered under pragmatics).
Não posso ir, pois tenho uma reunião.
I can't go, for I have a meeting.
Ele ficou em casa, pois estava doente.
He stayed home, since he was sick.
Portanto, logo, assim all mean therefore / so / thus, drawing a conclusion from the first clause. Portanto is the most general; logo is slightly more formal; assim is more about consequence than pure logic.
Penso, logo existo.
I think, therefore I am.
Está a chover muito; portanto, cancelamos o piquenique.
It's raining a lot; therefore, we're cancelling the picnic.
Perdi o autocarro; assim, cheguei atrasado.
I missed the bus; thus, I arrived late.
Punctuation in compound sentences
Punctuation in Portuguese coordinate sentences follows a few simple conventions.
Comma before mas, porém, contudo, todavia
Adversative conjunctions are almost always preceded by a comma — the contrast is strong enough to warrant a pause.
Queria ajudar-te, mas não tenho tempo.
I wanted to help you, but I don't have time.
O filme é longo, porém, vale a pena.
The film is long, however, it's worth it.
Comma before e — usually not, but sometimes yes
Unlike English, Portuguese normally does not put a comma before e between the last two items of a list or before a simple additive clause.
Comprei pão, queijo e fiambre.
I bought bread, cheese, and ham.
However, a comma appears before e when the clauses have different subjects and are longer, or when the second clause introduces new information with its own rhythm.
A Joana saiu de casa cedíssimo, e o marido acabou por adormecer outra vez.
Joana left home very early, and her husband ended up falling asleep again.
Semicolons with formal adversatives
Porém, contudo, todavia are often preceded by a semicolon (or full stop) rather than a comma — they carry enough weight to separate their clause strongly.
O relatório é bom; porém, falta-lhe uma conclusão.
The report is good; however, it lacks a conclusion.
Compound vs. complex sentences
It is worth sharpening the difference between coordination and subordination with side-by-side pairs. The same idea often has both a compound and a complex version, and the nuance differs.
| Compound (coordination) | Complex (subordination) |
|---|---|
| Estou cansado, mas vou trabalhar. | Embora esteja cansado, vou trabalhar. |
| I'm tired, but I'm going to work. | Even though I'm tired, I'm going to work. |
| Chegou a primavera e os dias já estão maiores. | Já que chegou a primavera, os dias estão maiores. |
| Spring came and the days are longer. | Since spring came, the days are longer. |
Coordination keeps both ideas at equal rank; subordination explicitly marks one as the grammatical frame for the other. The subordinate version often feels more formal or carries more explicit logical commitment.
Stacking more than two clauses
Compound sentences can chain multiple coordinated clauses. Portuguese handles this cleanly, especially with e.
Acordei, tomei o pequeno-almoço, saí de casa e apanhei o comboio das oito.
I woke up, had breakfast, left home, and caught the eight o'clock train.
Only the final clause in a chain takes the conjunction; the earlier clauses are separated by commas. This is the Portuguese list-like pattern — a row of actions ending with e before the last.
You can also mix conjunctions when each clause has a distinct logical relationship.
Liguei várias vezes, mas ninguém atendeu; por isso, deixei uma mensagem.
I called several times, but no one answered; so I left a message.
Here mas marks contrast and por isso (an adverbial phrase functioning like portanto) marks consequence. Each coordinator does its own work.
Asyndetic coordination: coordination without a conjunction
Portuguese also tolerates asyndeton — stringing clauses together with only commas, no overt conjunction. This is common in literary style and in emphatic speech, producing a rapid, weighty effect.
Vim, vi, venci.
I came, I saw, I conquered.
Chegou, bateu à porta, entrou sem dizer palavra.
He arrived, knocked at the door, went in without a word.
The clauses are still coordinated — each is independent, and an e could legally appear before the last one — but the writer has chosen to suppress it for rhythm.
Shared elements and ellipsis
When two coordinated clauses share a subject, an object, or a verb, Portuguese can omit the repeated element in the second clause. This makes compound sentences compact and natural.
Shared subject
A Marta chegou cedo e (ela) começou logo a trabalhar.
Marta arrived early and (she) started working right away.
O gato dormiu toda a tarde e acordou com fome.
The cat slept all afternoon and woke up hungry.
Because Portuguese is a pro-drop language, the subject of the second clause is typically omitted when it refers to the same person as the first. Repeating the subject pronoun (ela, ele) sounds unnatural unless you are marking contrast.
Shared verb
A Ana quer café e a Sofia, chá.
Ana wants coffee and Sofia, tea.
Ontem choveu muito; hoje, não.
Yesterday it rained a lot; today, not.
In the first example, quer is understood in the second clause — a compact construction that would be ungrammatical in English without repeating wants. The comma stands in for the elided verb. Portuguese writers use this ellipsis especially in parallel structures.
Shared object
Comprei e li o livro no mesmo dia.
I bought and read the book on the same day.
Vimos e ouvimos tudo da varanda.
We saw and heard everything from the balcony.
When two verbs share an object, Portuguese coordinates them directly without restating the object. This mirrors English bought and read — a compact verbal coordination.
Correlative pairs: extended coordinating structures
Beyond single conjunctions, Portuguese has several correlative pairs that bracket their clauses for balance or emphasis. These function as coordinators even though they span two positions in the sentence.
| Correlative | Meaning |
|---|---|
| ou... ou | either... or |
| nem... nem | neither... nor |
| não só... mas também | not only... but also |
| tanto... como | both... and |
| quer... quer | whether... or (alternatives) |
| já... já | now... now (literary) |
Não só aprendeu português como também se apaixonou pelo país.
Not only did he learn Portuguese, he also fell in love with the country.
Tanto o João como a Ana concordaram.
Both João and Ana agreed.
Quer vás de carro, quer vás a pé, chegarás a tempo.
Whether you go by car or on foot, you'll arrive on time.
These correlatives are especially common in formal writing and speechmaking, where the balanced structure adds rhetorical weight. Não só... mas também is the signature move of the essayist.
Register and word choice across compound sentences
The coordinators of Portuguese cluster into register tiers, and picking one over another is always a stylistic choice.
| Casual | Neutral | Formal |
|---|---|---|
| mas | mas / no entanto | porém / contudo / todavia |
| e | e | e bem assim / ademais |
| então, por isso | portanto | logo, destarte, assim sendo |
| ou | ou | ou ainda / ou bem |
In a WhatsApp message to a friend, you will write Estou cansado, mas vou sair and nothing else. In a formal letter, you might write Estou cansado; porém, vou sair. Both express the same relationship; the first is intimate, the second is measured.
Coordinated questions and commands
Coordination applies not only to statements but also to questions and imperatives, with each clause preserving its own mood.
Queres café ou preferes chá?
Do you want coffee, or would you prefer tea?
Liga-me amanhã e diz-me tudo.
Call me tomorrow and tell me everything.
Não grites e não batas à porta.
Don't shout and don't slam the door.
The coordinator simply joins two units of the same sentence type. The mood (interrogative, imperative, negative) belongs to each clause individually and stays intact.
Common Mistakes
❌ Estou cansado mais vou trabalhar.
Incorrect — mais means 'more', not 'but'.
✅ Estou cansado, mas vou trabalhar.
I'm tired, but I'm going to work.
English speakers reading Portuguese sometimes confuse mas (but) with mais (more). They are different words with different meanings. Coordinating contrast is mas; the quantifier more is mais.
❌ Ou vamos de carro ou vamos de comboio ou vamos a pé ou...
Awkward — English-style chaining of ou is uncommon.
✅ Podemos ir de carro, de comboio ou a pé.
We can go by car, by train, or on foot.
For three or more alternatives, Portuguese treats them as a list with commas and a final ou, just like e with additions. Repeated ou... ou... ou works only for binary emphatic either/or — stretching it across multiple items sounds unidiomatic.
❌ Não fumo e não bebo.
Awkward — negative additive should use nem.
✅ Não fumo nem bebo.
I don't smoke and I don't drink.
Chaining two negatives with e is grammatically possible but sounds clunky. Portuguese prefers nem — it signals both the addition and the polarity in a single word.
❌ Tenho fome, portanto eu vou comer agora.
Redundant — unnecessary subject pronoun after portanto.
✅ Tenho fome, portanto vou comer agora.
I'm hungry, so I'm going to eat now.
Because Portuguese is a pro-drop language, inserting eu after the conjunction adds nothing and reads as translated-from-English. Drop the subject pronoun unless it is carrying contrastive weight.
❌ Ela ligou, mais ninguém atendeu.
Incorrect — same mais/mas confusion.
✅ Ela ligou, mas ninguém atendeu.
She called, but no one answered.
Spelling check: mas (but) versus mais (more). The letter i is the only difference, but the meanings are unrelated.
Key takeaways
- A compound sentence joins two or more independent clauses — each could stand alone.
- The main coordinators are e (and), mas (but), ou (or), nem (nor), pois (for), portanto/logo/assim (therefore).
- Register matters: mas works everywhere; porém, contudo, todavia belong to formal writing.
- Punctuation: comma before mas; no comma before e with the same subject; semicolon or full stop before high-register adversatives.
- Coordinators like nem and ou can pair up as correlatives — nem... nem, ou... ou — for emphatic negative or alternative chains.
- Compound sentences are structurally flat: no clause depends on another. That is what distinguishes them from complex sentences, where one clause is embedded in or dependent on the other.
Related Topics
- Simple SentencesA1 — Single-clause sentences in Portuguese — the smallest complete unit of meaning, with one subject and one main verb.
- Complex SentencesA2 — Main clauses with dependent subordinate clauses joined by que, quando, se, porque, embora, and other subordinators.
- Portuguese Sentence Structure OverviewA1 — An introduction to how Portuguese sentences are built — word order, sentence types, and what makes Portuguese different from English.
- Coordinating Conjunctions (E, Ou, Mas, Nem)A1 — Joining independent clauses of equal weight — the four workhorses *e*, *ou*, *mas*, and *nem*, plus the semi-coordinators *também* and *bem como*.
- Adversative Conjunctions (Mas, Porém, Contudo, Todavia)A2 — Expressing contrast and opposition in Portuguese — from the everyday *mas* to the formal *porém*, *contudo*, *todavia*, and *não obstante*.
- Conjunctions OverviewA2 — Words that connect clauses and sentences in Portuguese — from simple *e* and *mas* to the formal *uma vez que* and *dado que*.