The meaning behind the choice
Portuguese can mark the subject inside an infinitive phrase. This is especially useful when the infinitive’s subject differs from the main clause or needs emphasis.
Do not begin by translating one English word into Portuguese. Begin with the relationship you want to express: destination or purpose, state or manner, familiarity or factual knowledge, movement toward or fixed location. The form becomes easier when the meaning is clear.
- Clarify a different subject
- Common after para, antes de, depois de, sem, and por
- Eu and ele/ela often have the unchanged infinitive form
- Nós adds -mos; eles/elas add -em
- Do not inflect automatically when the subject is already obvious and unchanged
- Compound personal infinitives use ter + participle
Examples you can reuse
Read each pair aloud and explain why the highlighted choice fits the message. Then change the person, time, place, or object while preserving the same contrast.
É importante você confirmar o horário.
It is important for you to confirm the time.
Você is the infinitive’s subject.
Antes de sairmos, feche a janela.
Before we leave, close the window.
Sairmos marks nós.
Eles agradeceram por termos ajudado.
They thanked us for having helped.
Compound personal infinitive.
Trouxe café para vocês provarem.
I brought coffee for you all to try.
Provarem marks vocês.
The mistakes learners make most often
Most errors happen when a learner memorizes a translation but misses the context. Use these warning signs to slow down and choose deliberately.
- Writing para mim fazer in formal standard Portuguese
- Inflecting every infinitive
- Forgetting irregular stems follow the future subjunctive pattern
- Confusing the personal infinitive with a conjugated main verb
A five-minute practice loop
Say the answer before looking at a rule. Explain your choice in one short phrase. Change one detail and answer again. The goal is not to recite terminology; it is to recognize the meaning quickly enough for conversation.
- Write one para eu and one para nós sentence
- Change the subject from você to vocês
- Use antes de with a different subject
- Create one compound form with termos