Both pero and sino translate into English as but, however, their usage is not interchangeable.  Let’s start with pero. The word pero, meaning but, is an adversative conjunction: adversative because pero redirects the preceding statement; pero is at the same time a conjunction because it joins the preceding clause to the one that follows it. Both the first and second clauses contain a conjugated verb. Use pero whenever the first clause is an affirmative statement and when the second clause does not contradict the first, but provides additional information:

Queremos comer, pero primero tenemos que ir a la tienda.

We want to eat, but first, we have to go to the store.

Ella hace ejercicios, pero su esposo, no.

She works out, but her husband doesn’t.

However, whenever the first clause is negative, use sino, which is also an adversative conjunction.  What distinguishes their usage is that when the bit of information that follows contradicts or corrects the first clause.  Furthermore, when no conjugated verb is used to introduce the contradictory information, sino is used alone, followed by either a noun, an adjective, an adverb or an infinitive. It translates into English as but rather:

Contradiction by a noun

No soy periodista sino poeta.

I’m not a journalist, but rather a poet.

Contradiction by an adjective

Ella no es rubia sino pelirroja.

She’s not a blonde, but rather a redhead.

Contradiction by an adverb

No hacían la tarea rápidamente, sino lentamente.

They weren’t doing the task quickly, but rather, slowly.

Contradiction by an infinitive

Ellos no quieren bailar sino cantar.

They don’t want to dance, but rather to sing.

Finally, whenever such negative statements are followed by a clause – which by definition, must contain a conjugated verb – then use sino que.  Keep in mind that one of the many functions of que is to introduce a subordinated clause, linking it to a preceding, or main clause.  Since an infinitive was the contradictory element in the third example above using sino, observe what Spanish must do if the sentence is rewritten using conjugated verbs in both clauses:

Ellos no bailan, sino que cantan.

They aren’t dancing, but rather singing.

With a little practice, and attention to what you’re really saying, these models will serve you well if you are teaching Spanish or learning it as a second language.

© 2019, Translation Skills Training (TST).