3Module 7
The Personal Infinitive
O Infinitivo Pessoal
Key Concept
While most languages have only one infinitive form, Portuguese adds personal endings to the infinitive so it can have its own subject. This avoids ambiguity and makes sentences more compact. For example, 'É difícil eles compreenderem' (It's hard for them to understand) uses a conjugated infinitive instead of 'É difícil que eles compreendam'.
Key Phrase — Try saying it!
Para nós aprendermos, temos de praticar.
1Personal Infinitive Conjugation
| Person | Ending | Falar | Comer | Partir |
|---|---|---|---|---|
| Eu | — (no change) | falar | comer | partir |
| Tu | -es | falares | comeres | partires |
| Ele/Ela | — (no change) | falar | comer | partir |
| Nós | -mos | falarmos | comermos | partirmos |
| Eles/Elas | -em | falarem | comerem | partirem |
2When to Use the Personal Infinitive
When the subject of the infinitive differs from the main clause subject, the personal infinitive clarifies who does what.
The personal infinitive avoids ambiguity about who didn't know.
Antes de + personal infinitive is very common when subjects differ.
The personal infinitive indicates a completed action by a specific subject.
Even when the subject is the same, the personal infinitive can be used for emphasis.
Ao + personal infinitive expresses simultaneous or immediately preceding actions.
Por + personal infinitive expresses cause or reason.
Até + personal infinitive sets a temporal boundary.
Impersonal expressions followed by a subject + infinitive require the personal form.