When a relative clause contains a verb or expression that requires a preposition, Portuguese keeps the preposition attached to the relative pronoun, at the beginning of the clause — never stranded at the end, as English often does. English cheerfully says "the house I live in" or "the person I'm talking about" with the preposition hanging at the end. Portuguese does not allow this. The preposition must sit in front of the relative pronoun: a casa *em que vivo, a pessoa **de quem estou a falar. The choice of pronoun — *que, quem, or o qual — depends on whether the antecedent is a thing or a person, on the preposition itself, and on the register. Learning these patterns is what pushes your Portuguese from basic to fluent: almost every spoken sentence of any length will contain one.
The fundamental rule — no stranded prepositions
This is the single most important lesson of this page. Portuguese never leaves a preposition dangling at the end of a relative clause. The preposition goes in front of the relative pronoun.
A casa em que vivo é pequena.
The house I live in is small. (English strands the preposition; Portuguese fronts it)
O livro de que te falei é este.
The book I told you about is this one.
A pessoa com quem falo todos os dias é a minha vizinha.
The person I talk to every day is my neighbour.
O projeto em que estou a trabalhar termina em junho.
The project I'm working on ends in June.
If you find yourself wanting to end a relative clause with a preposition — "a casa que vivo em," "o livro que te falei de" — stop. Move the preposition to the front of the pronoun. The correct Portuguese always looks like preposition + pronoun + rest of clause.
Choosing the pronoun: three options
After a preposition, you have three main choices:
- prep + que — for things (mandatory for things with short prepositions).
- prep + quem — for people (the standard choice after most short prepositions).
- prep + o qual / a qual / os quais / as quais — more formal; required for things or people after certain prepositions; useful for disambiguation.
The table below shows the division of labour.
| Preposition |
|
| Register |
|---|---|---|---|
| em (in, on) | em que | em quem | neutral |
| de (of, from, about) | de que | de quem | neutral |
| com (with) | com que | com quem | neutral |
| a (to, at) | a que | a quem | neutral |
| por (for, through) | por que | por quem | neutral |
| para (for, to) | para que / para o qual | para quem | neutral/formal |
| sem (without) | sem o qual | sem quem | formal |
| sobre (about, on) | sobre o qual | sobre o qual (rarely sobre quem) | formal |
| contra (against) | contra o qual | contra quem / contra o qual | formal |
| perante, segundo, mediante... | o qual | o qual | formal |
The patterns with short everyday prepositions (em, de, com, a, por) are used constantly in conversation. The patterns with longer or more literary prepositions (sobre, perante, mediante, segundo) belong to formal writing.
Preposition + que (for things)
With short prepositions and an inanimate antecedent, Portuguese uses prep + que. This is the workhorse pattern.
em que
em covers in, on, at in English. It joins with que to form em que — used whenever the verb or expression requires em.
A cidade em que nasci fica no norte do país.
The city I was born in is in the north of the country.
O momento em que o vi foi inesquecível.
The moment I saw him was unforgettable.
A situação em que me encontro é complicada.
The situation I find myself in is complicated.
Os anos em que vivi em Londres foram os mais felizes da minha vida.
The years I lived in London were the happiest of my life.
Time expressions take em que to mean when or in which: o dia em que, o ano em que, a altura em que.
Lembro-me do dia em que te conheci.
I remember the day I met you.
de que
de covers of, from, about. Many Portuguese verbs govern de — falar de (speak about), precisar de (need), gostar de (like), lembrar-se de (remember), depender de (depend on). When you use one of these verbs inside a relative clause about a thing, the relative is de que.
O livro de que te falei é este.
The book I told you about is this one. (falar de)
A viagem de que mais gostei foi a dos Açores.
The trip I liked most was the one to the Azores. (gostar de)
O assunto de que não quero falar agora é esse.
The subject I don't want to talk about right now is that one.
A ajuda de que precisas é fácil de encontrar.
The help you need is easy to find. (precisar de)
com que
com means with — and it is a very common preposition in relative clauses.
A caneta com que assinei o contrato foi um presente.
The pen I signed the contract with was a gift.
A facilidade com que ele resolve problemas é admirável.
The ease with which he solves problems is admirable.
O carinho com que fomos recebidos emocionou-nos.
The warmth with which we were welcomed moved us.
a que
a often appears with verbs like assistir a (attend), referir-se a (refer to), dedicar-se a (devote oneself to), responder a (respond to). The resulting a que is common in speech and writing alike.
O concerto a que fomos ontem foi incrível.
The concert we went to yesterday was incredible. (assistir a)
A causa a que me dedico é nobre.
The cause I'm devoted to is noble. (dedicar-se a)
por que and porque
These two look alike but are different. Por que (two words) means for which, through which, why. Porque (one word) is the conjunction because. In relative clauses, you want the two-word form.
A razão por que ele saiu é um mistério.
The reason why he left is a mystery.
As ruas por que passámos estavam desertas.
The streets we went through were deserted.
O motivo por que não vim foi o mau tempo.
The reason I didn't come was the bad weather.
sem que — a special case
Sem (without) combines with que in a particular way: sem que introduces a subjunctive clause meaning without ... -ing, rather than a strict relative. In true relative clauses about things, we usually say sem o qual:
O documento sem o qual não podemos prosseguir está em falta.
The document without which we cannot proceed is missing. (formal)
Saí sem que ele me visse.
I left without his seeing me. (sem que + subjunctive — not strictly a relative)
Preposition + quem (for people)
When the antecedent is a person and the clause needs a short preposition, Portuguese prefers prep + quem. This is the most idiomatic pattern for people after a, de, com, em, por, para.
a quem
A pessoa a quem entreguei a carta era o porteiro.
The person I handed the letter to was the doorman.
O colega a quem pedi ajuda reagiu mal.
The colleague I asked for help reacted badly.
O autor a quem dediquei o livro morreu no ano passado.
The author to whom I dedicated the book died last year.
de quem
O amigo de quem te falei chega hoje.
The friend I told you about arrives today.
A professora de quem mais gosto é a de história.
The teacher I like most is the history one.
A pessoa de quem estamos à espera chega em dez minutos.
The person we're waiting for arrives in ten minutes.
com quem
Os amigos com quem viajei eram do Porto.
The friends I travelled with were from Porto.
A rapariga com quem ele casou é francesa.
The girl he married is French.
O colega com quem partilho o gabinete está de férias.
The colleague I share the office with is on holiday.
para quem
O cliente para quem trabalho é alemão.
The client I work for is German.
A pessoa para quem comprei o presente já tem um igual.
The person I bought the present for already has an identical one.
em quem
Less common than the others, but useful with verbs like confiar em (trust in), pensar em (think of), acreditar em (believe in).
A pessoa em quem mais confio é a minha irmã.
The person I trust most is my sister.
O amigo em quem estava a pensar ligou-me.
The friend I was thinking about called me.
por quem
O colega por quem fiz o favor nem me agradeceu.
The colleague I did the favour for didn't even thank me.
A pessoa por quem mais me sacrifiquei nunca soube.
The person I sacrificed myself for the most never knew.
Preposition + o qual / a qual / os quais / as quais (formal)
The variable relative o qual agrees in gender and number with its antecedent. It has two main uses after prepositions:
- Required after long, multi-syllabic, or compound prepositions where que sounds clipped (sobre, contra, segundo, mediante, perante, através de, durante, desde, após, entre).
- Stylistic — chosen in formal written Portuguese even after short prepositions, especially in non-restrictive clauses, to sound more precise or elegant.
After long prepositions — required
O tópico sobre o qual discutimos ontem é controverso.
The topic we discussed yesterday is controversial.
A lei segundo a qual fomos julgados já foi revogada.
The law under which we were judged has already been repealed.
O regulamento perante o qual somos responsáveis mudou.
The regulation before which we are responsible has changed.
O meio através do qual nos conhecemos foi um amigo comum.
The medium through which we met was a mutual friend.
Os anos durante os quais vivi em Paris marcaram-me.
The years during which I lived in Paris marked me.
A época desde a qual não nos víamos parecia uma eternidade.
The period since which we hadn't seen each other seemed an eternity.
As a formal alternative in non-restrictive clauses
Even with short prepositions, formal writing sometimes prefers o qual:
A reunião, à qual assisti por vídeo, foi cancelada.
The meeting, which I attended by video, was cancelled. (à qual = a + a qual)
O contrato, pelo qual assumimos esta responsabilidade, vence em março.
The contract, by which we assumed this responsibility, expires in March. (pelo qual = por + o qual)
Contractions — very important
a + o qual, os quais contract: ao qual, aos quais. a + a qual, as quais contract: à qual, às quais. de + the forms contract: do qual, da qual, dos quais, das quais. em + the forms contract: no qual, na qual, nos quais, nas quais. por + the forms contract: pelo qual, pela qual, pelos quais, pelas quais.
These contractions are obligatory — writing de o qual or em o qual is an error.
O projeto no qual trabalho envolve três países.
The project I'm working on involves three countries.
A razão pela qual saí não é o que pensas.
The reason I left isn't what you think.
A decisão à qual chegámos é definitiva.
The decision we reached is final.
Os factos dos quais falamos são públicos.
The facts we are talking about are public.
Where o qual disambiguates
One of the strongest arguments for o qual is disambiguation. Because que and quem are invariable, they cannot tell you which of two possible antecedents they refer to. O qual agrees in gender and number, so it can.
Falei com a mãe do Pedro, *a qual estava muito preocupada.*
The feminine a qual unambiguously picks a mãe as the antecedent. Had you written o qual instead, it would point to o Pedro. With plain que, the sentence would be ambiguous.
Encontrei o pai da Ana, o qual me reconheceu imediatamente.
I met Ana's father, who recognised me immediately. (o qual = the father)
Encontrei o pai da Ana, a qual me reconheceu imediatamente.
I met Ana's father — and she (Ana) recognised me immediately. (a qual = Ana)
Word order inside the clause
One point that trips English speakers: once the preposition and relative pronoun are in place, the rest of the clause follows normal Portuguese word order (typically subject-verb-object, with the understood subject sometimes dropped).
O amigo com quem (eu) viajei trabalha em Berlim.
The friend I travelled with works in Berlin. (subject eu is understood)
A professora a quem a Maria entregou o trabalho é muito exigente.
The teacher to whom Maria handed in the assignment is very demanding.
Note that in the second example, a Maria is the subject of the relative clause, and she appears after the relative pronoun. The relative pronoun is not itself the subject of the clause — it is the indirect object (to whom).
Register: which pronoun when
As a quick practical guide:
- Everyday speech and informal writing: prep + que (things), prep + quem (people). These sound natural and are used constantly.
- Formal writing (journalism, essays, reports): prep + o qual appears frequently, especially in non-restrictive clauses and with longer prepositions.
- Academic, legal, and literary prose: o qual is fully at home. So are the rare combinations like perante a qual and em virtude dos quais.
A telltale sign of over-formality in a learner's Portuguese is over-using o qual in casual contexts. Most of the time, stick with com quem and em que.
Multiple prepositions, long-distance relatives
In complex sentences, the relative pronoun and its preposition may stretch far from the antecedent. Track the logic carefully.
A empresa com a qual negociámos o contrato no ano passado mudou de direção.
The company with which we negotiated the contract last year has changed management.
Os princípios sobre os quais se baseia a nossa política foram definidos em 1976.
The principles upon which our policy is based were defined in 1976.
Even in these long-form sentences, the rule holds: the preposition sits in front of the relative pronoun.
Common Mistakes
❌ A casa que vivo em é pequena.
Incorrect — Portuguese never strands the preposition at the end.
✅ A casa em que vivo é pequena.
The house I live in is small.
❌ O amigo que te falei de chegou ontem.
Incorrect — de must come before the relative pronoun.
✅ O amigo de quem te falei chegou ontem.
The friend I told you about arrived yesterday.
❌ A pessoa com que falo todos os dias é a minha vizinha.
Questionable — for people after short prepositions, quem is strongly preferred.
✅ A pessoa com quem falo todos os dias é a minha vizinha.
The person I talk to every day is my neighbour.
❌ O projeto em o qual trabalho é difícil.
Incorrect — em + o qual must contract to no qual.
✅ O projeto no qual trabalho é difícil.
The project I work on is difficult.
❌ O tópico sobre que discutimos era complicado.
Awkward — sobre demands o qual, not que.
✅ O tópico sobre o qual discutimos era complicado.
The topic we discussed was complicated.
❌ A caneta com quem escrevo foi um presente.
Incorrect — quem is only for people; use que for the pen.
✅ A caneta com que escrevo foi um presente.
The pen I'm writing with was a gift.
Key Takeaways
- Portuguese never strands a preposition at the end of a relative clause. The preposition sits in front of the relative pronoun.
- After short prepositions, use que for things and quem for people.
- After long or compound prepositions (sobre, perante, segundo, através de, durante), use o qual.
- O qual also appears in formal non-restrictive clauses and whenever gender/number agreement is useful to disambiguate.
- Contractions with a, de, em, por are obligatory: ao qual, à qual, do qual, na qual, pelo qual.
- The register test: everyday conversation uses em que, de que, com quem, a quem; formal writing uses sobre o qual, segundo o qual, perante o qual.
Related Topics
- Relative Clauses OverviewA2 — How relative clauses work in European Portuguese — que, quem, o qual, cujo, onde, and the restrictive vs non-restrictive distinction.
- Restrictive vs Non-Restrictive Relative ClausesB1 — The meaning difference — and the comma rule — between clauses that identify and clauses that merely comment.
- Relative Clauses with Cujo (Possessive)B2 — Building possessive relative clauses — the syntax, word order, and formal register of cujo-clauses.
- Relative Pronoun Que (The Most Common)A2 — The workhorse relative pronoun of Portuguese — used for people, things, and concepts, as subject or direct object of the relative clause
- Relative Pronoun Quem (Referring to People)B1 — The relative pronoun used specifically for people — mostly after prepositions or as a free relative meaning 'whoever'
- Relative Pronoun O Qual / A Qual (Formal with Prepositions)B2 — The variable, formal relative pronoun that agrees in gender and number — used mainly after prepositions and to resolve ambiguity