The second major home of the personal infinitive is as the subject of a sentence — most often the notional subject of an impersonal predicate like é importante, é preciso, é bom, é difícil, convém, é pena. Where English and Spanish must attach these predicates to a full que / that clause, Portuguese can use the personal infinitive to carry the subject directly into the verb form. The result is compact and everyday: é importante estudarmos, é bom vocês virem, é preciso eles saberem.
This page covers the main uses: the impersonal-predicate construction (by far the most common), the personal infinitive as a topic or stand-alone subject (lermos em voz alta ajuda a memorizar), and the related absolute-clause construction with the personal gerund (estando eles aqui, podemos começar). It also lays out the choice between the personal infinitive and que + subjunctive in these contexts — both are grammatical, and knowing when to prefer each is a B2 skill.
The core construction: é + adjective/noun + personal infinitive
The basic pattern is: an impersonal predicate (typically é + adjective or é + noun), followed directly by the personal infinitive of the action being evaluated.
É importante estudarmos um pouco todos os dias.
It's important that we study a little every day.
É bom vocês virem jantar connosco.
It's nice that you're coming to have dinner with us.
É difícil eles concordarem em alguma coisa.
It's difficult for them to agree on anything.
É raro termos tempo para jantares em família.
It's rare for us to have time for family dinners.
The structure is lean: é + evaluative adjective + personal infinitive. No que, no subjunctive, no finite clause at all. The personal infinitive carries the subject via its ending, and the sentence lands in one smooth arc.
The most common impersonal triggers
A handful of impersonal expressions are the heavy lifters of this construction. Learning these by heart will cover most of the territory.
é importante / é preciso / é necessário / é fundamental
These mark necessity or priority. They accept both the personal infinitive and que + subjunctive.
É importante chegarmos a horas.
It's important that we arrive on time.
É preciso os alunos estudarem todos os dias.
The students need to study every day.
É fundamental percebermos o que está em jogo.
It's fundamental for us to understand what's at stake.
É necessário fazeres tudo com calma.
It's necessary that you do everything calmly.
é bom / é mau / é pena
These are evaluative: they express that something is good, bad, or regrettable.
É bom termos amigos em quem podemos confiar.
It's nice that we have friends we can trust.
É mau eles passarem tanto tempo em frente ao computador.
It's bad that they spend so much time in front of the computer.
É pena não poderes vir à festa.
It's a shame you can't come to the party.
É pena o João ter perdido a oportunidade.
It's a shame João missed the opportunity.
é difícil / é fácil / é possível / é impossível / é provável
These evaluate likelihood or feasibility.
É difícil acreditarmos em tudo o que nos dizem.
It's hard for us to believe everything we're told.
Não é fácil tu perceberes, eu sei.
It's not easy for you to understand, I know.
É possível chegarmos a tempo se sairmos já.
It's possible for us to arrive on time if we leave now.
É impossível eles resolverem isto sozinhos.
It's impossible for them to resolve this on their own.
É provável vocês terem razão.
It's likely that you're right.
convém / basta / resta
These are impersonal in a different way — they carry their own semantics without needing an adjective.
Convém chegares cedo para garantir lugar.
It's advisable that you arrive early to guarantee a spot.
Basta dizermos a verdade.
It's enough for us to tell the truth.
Resta vermos se a empresa aceita a proposta.
It remains to be seen whether the company accepts the proposal.
é hora de / é altura de / está na hora de
These temporal impersonals are especially welcoming to the personal infinitive in everyday speech.
É altura de tomares uma decisão.
It's time for you to make a decision.
Já é hora de eles assumirem a responsabilidade.
It's about time they took responsibility.
The choice: personal infinitive vs que + subjunctive
After impersonal expressions, both structures are grammatical. Here is the side-by-side:
| Personal infinitive | Que + subjunctive |
|---|---|
| É importante tu estudares. | É importante que tu estudes. |
| É melhor nós irmos embora. | É melhor que nós vamos embora. |
| É preciso eles saberem. | É preciso que eles saibam. |
| Convém chegares cedo. | Convém que chegues cedo. |
| É pena ela não vir. | É pena que ela não venha. |
Both versions of each sentence mean the same thing. The difference is stylistic.
The personal infinitive is lighter and more colloquial. It is the default in speech. It also tends to win when the subject is very short and clear — tu, nós, eles, ela.
Que + subjunctive is marginally more formal. It is more common in writing, in careful speech, in speeches and official communications. It also wins when the speaker wants to slightly emphasize the subject, or when the finite verb carries its own aspectual or modal nuance that the infinitive cannot express (for example, distinguishing between venha and tenha vindo — "come" vs "have come").
When the subject is generic: use the bare infinitive
A crucial contrast: when an impersonal expression is making a universal claim — something true for anyone, not a specific subject — the bare impersonal infinitive wins over both options.
É importante beber muita água.
It's important to drink a lot of water. (universal, any person)
É preciso ter paciência.
It's necessary to have patience. (advice for anyone)
Não é fácil falar em público.
It's not easy to speak in public.
Switching to the personal infinitive (é importante bebermos muita água) narrows the claim to nós specifically. Switching to que + subjunctive (é importante que se beba) would force you into an impersonal se construction. The bare infinitive is the cleanest solution for a truly universal statement.
| Construction | Implied subject | Example |
|---|---|---|
| Bare infinitive | Generic / universal | É importante estudar. (anyone) |
| Personal infinitive | Specific (inflection) | É importante estudarmos. (we) |
| Que + subjunctive | Specific (finite verb) | É importante que estudemos. (we) |
The axis is generic vs specific, not formal vs informal. A speaker giving general life advice ("it's important to drink water") will use the bare infinitive. A speaker making a claim about their own household ("it's important that we drink water") will use the personal infinitive or que + subjunctive.
The personal infinitive as a topic
The personal infinitive can also function as the subject of a non-impersonal verb, as the topic of a sentence.
Lermos em voz alta ajuda a memorizar.
Reading out loud (by us) helps with memorizing.
Fazermos isso sozinhos é um desafio enorme.
Us doing this alone is a huge challenge.
Irmos ao mesmo restaurante todas as semanas é aborrecido.
Us going to the same restaurant every week is boring.
Dizerem isso em público foi uma falta de educação.
Them saying that in public was rude.
Here the inflected infinitive is the grammatical subject of the main verb (ajuda, é, foi). This is an advanced and slightly literary construction — in everyday speech, speakers often rephrase this as o facto de + personal infinitive (o facto de lermos em voz alta ajuda...), which sounds more conversational.
O facto de termos falado com ele foi decisivo.
The fact that we spoke with him was decisive.
O facto de ela não ter avisado é um problema.
The fact that she didn't warn us is a problem.
This o facto de + personal infinitive pattern is the workhorse in writing and professional speech; it gives the sentence a clearer anchor and avoids the slightly awkward bare-infinitive-as-topic structure.
Absolute clauses with the personal gerund
The personal infinitive's close cousin is the personal gerund — a gerund that also conjugates for person. It appears mainly in absolute clauses, where it introduces a subordinate clause without a conjunction.
Estando eles aqui, podemos começar.
With them being here, we can begin.
Chovendo tanto, ninguém vai à praia.
With it raining so much, no one is going to the beach.
Tratando-se de uma emergência, ligámos logo.
It being an emergency, we called right away.
Não havendo objeções, a proposta foi aprovada.
There being no objections, the proposal was approved.
These are literary or formal constructions — they are more common in newspaper prose, legal writing, and elevated speech than in everyday conversation. In casual contexts, Portuguese speakers usually rephrase with a full clause: como eles estão aqui, podemos começar ("since they're here...").
Learn to recognize these absolute clauses in reading; in speech, the preposition-plus-personal-infinitive or como + finite clause constructions are what you will produce.
The personal infinitive in place of a clause: practical contexts
Beyond the classic é + adjective templates, the personal infinitive frequently stands in for a whole subject clause in other constructions.
With aparent subject-raising
Parece-me ser importante eles ouvirem a outra parte.
It seems to me important for them to hear the other side.
Acho útil discutirmos isto abertamente.
I think it's useful for us to discuss this openly.
After "aquilo que" and clefting
O que importa é chegarmos a um consenso.
What matters is for us to reach a consensus.
O problema é eles não terem sido informados.
The problem is that they weren't informed.
These sentences have the personal infinitive as a predicative complement after ser, following a topicalized expression like o que importa or o problema. The result is compact and idiomatic.
In nominal constructions
A ideia de irmos juntos foi dele.
The idea of us going together was his.
A possibilidade de saírem ainda hoje não está posta de parte.
The possibility of them leaving today is not off the table.
Here the personal infinitive is the complement of a preposition (de) governed by a noun (ideia, possibilidade). This is everywhere in professional writing — o direito de, a intenção de, a vontade de, o prazer de — all happily take a personal infinitive with a subject change.
Comparison with other Romance languages
Because English speakers routinely learn Spanish before Portuguese, the Spanish comparison is worth making explicit. Everywhere Portuguese has a choice, Spanish is forced into que + subjuntivo:
| Spanish | Portuguese |
|---|---|
| Es importante que estudiemos. | É importante estudarmos. / É importante que estudemos. |
| Es necesario que sepan la verdad. | É preciso saberem a verdade. / É preciso que saibam a verdade. |
| Es difícil que lleguemos a tiempo. | É difícil chegarmos a tempo. / É difícil que cheguemos a tempo. |
| Es hora de que se vayan. | É hora de se irem embora. / Está na hora de irem. |
A Spanish-speaking learner who defaults to que + subjuntivo in Portuguese will produce grammatically correct but stylistically stiff Portuguese. Training the ear to reach for the personal infinitive is the single biggest step toward sounding native.
Register: not just spoken Portuguese
A common misconception: the personal infinitive is "informal" and que + subjunctive is "formal." This is wrong. The personal infinitive appears throughout formal writing, news articles, academic prose, legal documents, and official communications. A recent statement from the Portuguese government might begin with É imperativo procedermos com cautela ("It is imperative that we proceed with caution") — using the personal infinitive, not que procedamos. Both registers use both structures.
The personal infinitive is not a folk feature; it is a core grammatical resource of Portuguese, and educated speakers in every register rely on it constantly. The register axis runs between clausal (with que and a finite verb, more explicit) and compact (with the personal infinitive, more economical). Both are everywhere.
Common Mistakes
❌ É importante que estudarmos todos os dias.
Incorrect — you cannot combine que with a personal infinitive.
✅ É importante estudarmos todos os dias.
It's important that we study every day. (personal infinitive)
✅ É importante que estudemos todos os dias.
It's important that we study every day. (que + present subjunctive)
The single most common error in this territory. Que introduces a finite clause; the personal infinitive is non-finite. They cannot coexist in the same subordinate clause.
❌ É fundamental a equipa trabalharem em conjunto.
Agreement error — a equipa is singular, so the verb should be singular (trabalhar).
✅ É fundamental a equipa trabalhar em conjunto.
It's fundamental for the team to work together.
The personal infinitive agrees with its subject in person and number. A collective noun like a equipa is grammatically singular, so the bare infinitive is correct. The plural -em ending would only be right for a plural subject.
❌ É bom vocês virdes visitar-nos.
Archaic — virdes is the old 2pl form (vós), which is no longer current. Use virem for vocês.
✅ É bom vocês virem visitar-nos.
It's nice that you're coming to visit us.
Vocês is grammatically third-person plural, so it takes the -em ending. The old vós form virdes exists in hymns, legal Portuguese, and northern dialects but is not current in standard European Portuguese.
❌ É importante beber muito água.
Agreement error — água is feminine, so the adjective muito must agree: muita.
✅ É importante beber muita água.
It's important to drink a lot of water.
A broader Portuguese mistake rather than a personal-infinitive-specific one, but it comes up constantly because this sentence pattern is so common.
❌ É difícil que concordemos em tudo, mas tentamos.
Overuse of que + subjunctive — natural Portuguese would prefer the personal infinitive here.
✅ É difícil concordarmos em tudo, mas tentamos.
It's hard for us to agree on everything, but we try.
Both are grammatical, but que concordemos is the stiffer, more Spanish-influenced option. A native European Portuguese speaker in conversation would almost certainly choose concordarmos. This is a training point, not a hard error.
Key takeaways
- The personal infinitive frequently serves as the subject of impersonal predicates: é importante estudarmos, é bom vocês virem, é preciso sabermos.
- It competes with que + subjunctive in these contexts. Both are grammatical; the personal infinitive is lighter and more common in everyday speech, que + subjunctive marginally more formal.
- For generic, universal claims ("it's important to X" for anyone), use the bare infinitive — neither the personal infinitive nor que + subjunctive.
- The personal infinitive can also act as the topic of a sentence (lermos em voz alta ajuda a memorizar) and as the complement of nouns (a ideia de irmos juntos).
- Absolute clauses with the personal gerund (estando eles aqui) are a literary / formal extension of the same logic.
- You cannot combine que with a personal infinitive. They are mutually exclusive.
- This is not an "informal" feature — educated Portuguese speakers use the personal infinitive constantly in all registers.
This concludes the dedicated personal-infinitive set. For the bigger picture of when to pick infinitive vs subjunctive across all contexts, see subjunctive vs infinitive. For the paradigm drill, return to formation.
Related Topics
- Personal Infinitive: OverviewB1 — The infinitivo pessoal — an infinitive that conjugates for person and number — is Portuguese's signature grammatical feature, and one of the things that makes the language feel unlike the rest of Romance.
- Personal Infinitive: FormationB1 — How to build the infinitivo pessoal: take the infinitive and add the personal endings -es, -mos, -em. No stem changes, no irregularities — the only exception is pôr, which keeps its circumflex.
- Personal vs Regular Infinitive: When to InflectB1 — The decision rules for choosing between the impersonal (bare) infinitive and the personal (inflected) infinitive — the most consulted page in this set.
- Personal Infinitive After PrepositionsB1 — The most common use of the infinitivo pessoal: after para, sem, antes de, depois de, até, and ao. Full examples of each, plus clitic placement with pronominal verbs.
- Subjunctive vs InfinitiveB2 — When Portuguese uses an infinitive — impersonal or personal — where other Romance languages force a subjunctive, and how to pick correctly between que + conjuntivo and the infinitive.
- Impersonal Expressions (É necessário que, É possível que)B1 — The subjunctive after impersonal É + adjective/noun + que expressions in European Portuguese, with the crucial contrast between judgment and certainty.