A compound sentence is two (or more) complete, independent sentences joined into one with a coordinating conjunction. The key word is independent: each half could stand alone as its own sentence, and neither is grammatically subordinate to the other. Eu trabalho and ela estuda are both full sentences; glue them with e and you get the compound sentence Eu trabalho e ela estuda. This is the opposite of subordination, where one clause leans on another — see Complex Sentences for that contrast.
What "coordination" means
In coordination, the two clauses are equals. Remove the conjunction and you have two grammatical sentences:
Eu trabalho e ela estuda.
I work and she studies.
Split it: Eu trabalho. / Ela estuda. Both stand alone. That is the test for coordination. Contrast this with subordination, where one half collapses on its own (porque ela estuda — "because she studies" — is not a complete thought).
The main coordinating conjunctions
Portuguese coordinators sort into a few semantic groups. Here are the everyday ones.
| Conjunction | Meaning | Relationship | Register |
|---|---|---|---|
| e | and | addition | neutral |
| nem | nor / and not | negative addition | neutral |
| mas | but | contrast | everyday |
| porém / contudo / todavia | however / yet | contrast | formal |
| ou | or | alternative | neutral |
| então / logo | so / therefore | conclusion | então: everyday; logo: formal |
| pois | for / because (explanatory) | justification | formal/literary |
Addition: e and nem
E simply adds one clause to another.
Ela cozinhou o jantar e eu lavei a louça.
She cooked dinner and I washed the dishes.
Nem is the negative counterpart — it means "and not" or "nor," and it already contains the negation, so you do not add a second não.
Ele não fuma nem bebe.
He doesn't smoke or drink.
Não tenho tempo nem dinheiro.
I have neither time nor money.
For emphasis, both ideas can take nem...nem: Nem fuma nem bebe ("He neither smokes nor drinks"). This is a correlative pair — see Correlative Structures.
Contrast: mas and porém
Mas is the everyday "but" — the one you reach for in conversation.
Eu queria ir, mas estava muito cansado.
I wanted to go, but I was very tired.
Porém, contudo, and todavia mean the same thing but belong to a more formal, written register. Crucially, porém is mobile — it can sit inside the second clause, not just at the boundary, which mas cannot do.
O projeto era ambicioso; o orçamento, porém, era limitado.
The project was ambitious; the budget, however, was limited.
Alternative: ou
Ou offers a choice between clauses.
A gente sai agora ou esperamos parar de chover?
Do we leave now or wait for the rain to stop?
Doubled as ou...ou it stresses the exclusivity: Ou você estuda ou você trabalha ("Either you study or you work").
Conclusion and justification: então and pois
Então draws a conclusion — "so," "therefore" — and is thoroughly conversational.
Estava chovendo, então fiquei em casa.
It was raining, so I stayed home.
Pois, when it links two independent clauses, gives the reason for the first and is distinctly formal or literary. (Watch out: pois é and pois não are separate fixed expressions in speech.)
Devemos partir cedo, pois a viagem é longa.
We should leave early, for the journey is long.
Comma usage
The comma rules differ in instructive ways from English. Before e joining two clauses, Portuguese generally uses no comma — the opposite of the American English "comma before and" habit.
Ele abriu a porta e entrou.
He opened the door and went in.
But before contrastive coordinators (mas, porém, contudo) and conclusive ones (então, logo, pois), a comma is used.
Estudei bastante, mas não passei na prova.
I studied a lot, but I didn't pass the test.
A comma does appear before e in one notable case: when the two clauses have different subjects, or to avoid ambiguity. O sol se pôs, e as luzes da cidade se acenderam ("The sun set, and the city lights came on") — here a comma is acceptable and often preferred for clarity.
| Conjunction | Comma before it? |
|---|---|
| e (same subject) | usually no |
| e (different subjects / clarity) | optional, often yes |
| mas, porém, contudo | yes |
| então, logo, pois | yes |
| ou (linking clauses) | optional |
Coordination vs. subordination at a glance
The whole point of this page is the contrast with the next one. In a compound sentence the clauses are peers; in a complex sentence one depends on the other.
Não fui à festa, mas liguei para a aniversariante.
I didn't go to the party, but I called the birthday girl. (coordination — two equal clauses)
Não fui à festa porque estava doente.
I didn't go to the party because I was sick. (subordination — 'because' clause depends on the main one)
In the first, both halves stand alone. In the second, porque estava doente cannot stand alone — it is subordinate. That structural difference, not the meaning, is what separates compound from complex.
Common Mistakes
❌ Ele não fuma e não bebe.
Incorrect — for negative coordination Portuguese prefers 'nem'.
✅ Ele não fuma nem bebe.
He doesn't smoke or drink.
❌ Não tenho nem tempo nem não tenho dinheiro.
Incorrect — 'nem' already carries the negation; don't pile on extra 'não'.
✅ Não tenho tempo nem dinheiro.
I have neither time nor money.
❌ Mandei a mensagem para minha amiga, porém ela não respondeu (in casual chat).
Incorrect register — 'porém' is formal; in conversation use 'mas'.
✅ Mandei a mensagem para minha amiga, mas ela não respondeu.
I texted my friend, but she didn't reply.
❌ Ele abriu a porta, e entrou.
Incorrect — no comma before 'e' when the subject is the same in both clauses.
✅ Ele abriu a porta e entrou.
He opened the door and went in.
The two habits to break from English: use nem (not e... não) for negative addition, and drop the comma before e when the subject stays the same. Get those right, and your compound sentences will read like a native's.
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Start learning Portuguese→Related Topics
- Simple SentencesA1 — A simple sentence has exactly one finite verb — one subject, one predicate. This page covers the copular, transitive, and intransitive patterns, plus why Brazilian Portuguese can drop the subject.
- Complex Sentences (Subordination)B1 — A main clause plus one or more dependent clauses — noun, adjective (relative), and adverbial — where the subordinator decides whether the verb is indicative or subjunctive.
- Correlative Structures (Não Só ... Mas Também)B2 — Paired connectors like 'não só ... mas também', 'tanto ... quanto', and 'nem ... nem' that link parallel elements — including the agreement traps they create.
- Sentence Structure: OverviewA2 — A map of Brazilian Portuguese sentence structure — the SVO default, the types of sentence (simple, compound, complex), the four functions (declarative, interrogative, imperative, exclamative), and the flexibility that lets subjects drop, topics front, and subjects follow the verb.