Preposition Errors

Prepositions are where English speakers leak the most errors, and the reason is almost always the same: you are translating the English structure word for word and assuming the preposition transfers. It does not. In Portuguese, a verb or adjective lexically selects its own preposition — the preposition is part of the word's dictionary entry, like a fixed accessory — and that selection rarely matches English. The single most useful habit you can build is to stop learning verbs as bare verbs and start learning them as verb + preposition units: not gostar, but gostar de; not precisar, but precisar de; not sonhar, but sonhar com.

This page collects the errors that come up again and again, shows the ❌ wrong form against the ✅ right one, and — crucially — explains the logic so you can predict the next case instead of memorizing endlessly.

"Gostar" always needs "de"

This is the number-one preposition error. In English you "like something" with no preposition. In Portuguese you cannot. Gostar obligatorily takes de, and de must then contract with any following article or demonstrative.

The contraction trips people up because the de seems to disappear: de + isso → disso, de + o filme → do filme, de + ela → dela. The preposition is still there; it has just fused.

"Precisar de" — the preposition you keep dropping

Same trap as gostar. English "need something" has no preposition, so learners write preciso ajuda. Portuguese requires de.

There is one nuance worth flagging honestly: when precisar is followed by a verb in colloquial Brazilian speech, the de is frequently dropped (preciso falar com você). But before a noun, the de is obligatory in every register. Don't generalize the dropped de from the verb case to the noun case.

"Pensar em," not "pensar de"

English "think of/about" pushes learners toward de. The Brazilian default for "have someone/something in mind" is pensar em.

Pensar de exists, but it means "to have an opinion about" and is almost always in a question with o que: O que você pensa disso? (What do you think of that?). For everyday "thinking about," it is em.

"Sonhar com," not "sonhar de"

To dream about something is sonhar com in Portuguese — never de, and never the English-style about.

"Casar com" and "depender de"

Two more fixed pairings that contradict English intuition. You marry with someone (casar com), and you depend of someone (depender de).

The reverse trap: prepositions English adds that Portuguese drops

The transfer error also runs the other way. English speakers insert a por because the English verb has a particle, but the Portuguese verb is transitive with no preposition.

Procurar (to look for) is the classic. English "look for" has a particle, so learners write procurar por. Standard Portuguese procurar takes a direct object — no preposition.

Procurar por is heard colloquially in Brazil, especially meaning "to ask after / search for a specific person," so it is not flatly ungrammatical — but the clean, always-correct default is no preposition. Esperar (to wait for / to hope for) behaves similarly: "wait for the bus" is esperar o ônibus, with the optional por far less common in BR than the English particle would suggest.

"Diferente de," not "diferente que"

Adjectives have government too. The comparison adjective diferente takes de, not que. The que error comes from over-extending the comparative pattern maior que, melhor que (which do use que).

"Chegar em" (Brazil) vs "chegar a" (prescriptive)

This one deserves honesty rather than a clean rule. Prescriptive grammar — the kind tested in Brazilian school exams and the concurso público — insists that chegar takes a: cheguei a São Paulo. But in actual spoken and informal written Brazilian Portuguese, virtually everyone says chegar em: cheguei em São Paulo.

Neither is "an error" in the sense the other items on this page are. Use chegar em in conversation without hesitation; switch to chegar a in a formal exam or an edited text where a grammar checker will be unforgiving.

"No fim de semana" — the fixed time expression

A small but frequent slip: "on the weekend" is no fim de semana, and the structure of the phrase is no fim *de semana (the *de belongs to fim de semana, "end of week"). Learners drop the de or swap the article.

Summary and recap

Preposition errors are not random — they are systematic transfers from English, and they fall into three buckets:

• Portuguese requires a preposition English lacks. Learn the unit: gostar de, precisar de (before nouns), pensar em, sonhar com, casar com, depender de, diferente de. The preposition often hides inside a contraction (de + isso = disso, de + a = da).
• English adds a particle Portuguese drops. Procurar, esperar, ouvir, pagar take a direct object — don't bolt on por.
• Brazilian usage diverges from prescriptive grammar. Chegar em dominates speech; chegar a is the exam-correct form. Match the register.

The fix is a mindset shift: a Portuguese verb's preposition is lexical, not logical, so memorize the verb and its preposition together as a single chunk, and stop expecting it to mirror English.

Common Mistakes