Complete Guide to Portuguese Verb Complements With Infinitives

Introduction

This guide explains how Portuguese verbs combine with infinitives to form complements, helping English-speaking learners master common structures in Brazilian Portuguese. Focusing on when to use the infinitive, differences between simple and personal infinitives, and common verbs that require infinitive complements, you will learn clear rules, examples, and usage notes to read and speak more naturally.

What is a verb complement with an infinitive?

A verb complement with an infinitive is a construction where one verb requires a following verb in the infinitive form to complete its meaning. In Portuguese, the infinitive appears as the basic verb form ending in -ar, -er, or -ir. These complements are essential to express intentions, obligations, preferences, perceptions, and more.

Key Portuguese terms

First appearance of the main Portuguese phrase: infinitivo. You will also see infinitivo pessoal and infinitivo impessoal explained below. Later appearances use infinitivo, infinitivo pessoal, and infinitivo impessoal.

Two types of infinitives in Portuguese

Portuguese has two main infinitive forms: the infinitivo impessoal (impersonal infinitive) and the infinitivo pessoal (personal infinitive). Understanding the difference is crucial for correct grammar and natural usage.

Infinitivo impessoal

The infinitivo impessoal is the base, unconjugated form used when there is no explicit subject or when the subject is general or unspecified. It is identical for all persons.

Examples:

comer, falar, estudar, partir.

Use the impersonal infinitive after modal-like verbs such as precisar, querer, dever, poder when the subject of both verbs is the same.

Example sentences:

Eu preciso estudar para a prova.

Ela quer viajar amanhã.

Infinitivo pessoal

The infinitivo pessoal is the infinitive conjugated to agree with a specific subject. It is used when the subject of the infinitive differs from the subject of the main verb or when emphasis on the subject of the infinitive is needed. These endings mirror present tense persons but remain infinitive-rooted: estudar -> estudar, estudarmos, estudarem, etc., with endings -mos, -es, -em depending on person.

Example sentence where subjects differ:

É importante eles chegarem cedo.

Note that the form chegarem agrees with eles.

When to use infinitive complements: common patterns

Below are common verb groups that require an infinitive complement. For each group, the rule and examples in Brazilian Portuguese are provided.

Verbs of intention and desire

Verbs like querer, gostar, preferir, and amar are followed by an infinitivo to express wants and preferences. Use the impersonal infinitive when the subject stays the same; use the personal infinitive if the subject differs or needs emphasis.

Examples:

Eu quero aprender português.

Nós preferimos viajar no inverno.

Ela quer que eu vá? -> Note: This uses a subordinate clause with que + subjunctive rather than infinitive because the subject of the subordinate clause differs; compare to Eu quero ir sozinha.

Verbs of obligation, necessity and possibility

Verbs like ter de, ter que, precisar, dever and poder take an infinitivo. Use impersonal forms when the subject is the same, and personal forms when subjects differ.

Examples:

Você tem que estudar mais.

Eles precisam resolver o problema.

Eu devo terminar hoje.

Perception verbs

Verbs of perception such as ver, ouvir, and sentir can be followed by an infinitive to describe ongoing or completed actions perceived by the subject.

Examples:

Eu ouvi cantar no ônibus.

Ela viu os meninos brincar no parque.

Verbs of causation and permission

Verbs like deixar, mandar, fazer often use an infinitive to indicate allowing, ordering, or making someone do something. With these verbs, the infinitive is common; when the subject of the infinitive differs, Portuguese may prefer an object + infinitive structure or use que + subjunctive.

Examples:

Ele deixou eu entrar? -> Informal; formally one might say Ele deixou-me entrar or Ele permitiu que eu entrasse.

A mãe mandou a criança lavar as mãos.

Verbs followed by prepositions + infinitive

Some verbs require a specific preposition before the infinitive. Common combinations include aprender a, começar a, conseguir a or chegar a, depending on region and register. Knowing these fixed patterns is important.

Examples:

Comecei a estudar português ontem.

Ela aprendeu a tocar violão.

Eles começaram a trabalhar cedo.

Personal infinitive: details and formation

The infinitivo pessoal is formed by adding endings to the infinitive stem. For regular verbs, endings are:

-ar verbs: eu cantar, nós cantarmos, eles cantarem

-er verbs: eu comer, nós comermos, eles comerem

-ir verbs: eu partir, nós partirmos, eles partirem

Note that the first person singular (eu) and third person singular (ele/ela) look like the impersonal form, so context determines interpretation. The personal infinitive is more frequent in European Portuguese but is also used in Brazilian Portuguese for clarity when subjects differ.

When subjects differ: examples

If the main clause and the infinitive clause have different subjects, use the infinitivo pessoal to show agreement.

Examples:

Foi importante eu estudar para a entrevista. -> eu estudar shows that the subject of estudar is eu.

Foi importante ele estudar para a entrevista. -> ele estudar would be acceptable in speech, but formally one uses ele estudar or ele ter estudado depending on tense nuance; alternatively, Foi importante que ele estudasse.

Fixed expressions with personal infinitive

Some phrases commonly use the personal infinitive for clarity or idiomaticity, like para eu fazer, sem nós sabermos, antes deles chegarem. These clarify who performs the action.

Examples:

Eles saíram sem nós sabermos.

Para eu terminar cedo, preciso me organizar.

Tense and aspect with infinitives

Infinitives can represent present or perfect actions depending on context or auxiliary constructions. To express anteriority (an action that happened before the main verb), Portuguese uses the compound infinitive: ter + past participle.

Compound infinitive for anterior actions

Form: ter + past participle. This behaves like an infinitive but indicates a completed action relative to the main verb.

Examples:

Ele afirmou ter visto o acidente. -> He claimed to have seen the accident.

Eu espero ter terminado até as cinco.

Progressive nuances

Although Portuguese lacks an infinitive progressive form, context or periphrastic constructions provide progressive meaning. For ongoing actions, Portuguese often uses estar + gerúndio rather than an infinitive.

Example:

Eu estou estudando agora. (not eu estar estudando)

Common pitfalls and differences with English

English speakers often transfer English patterns directly, but Portuguese has differences to note. For instance, English uses to + infinitive after many verbs; Portuguese may use que + subjunctive instead when subjects differ or when the meaning requires it.

Que + subjunctive vs infinitive

When the subject of the subordinate clause is different from the main clause, Portuguese commonly uses que + subjunctive instead of an infinitive, especially with verbs of influence, emotion, or desire.

Examples:

Eu quero que você venha amanhã. -> Here the subordinate subject is você, so que + subjunctive is natural.

Eu quero vir amanhã. -> If the subject remains eu, the infinitive is correct.

Using prepositions correctly

Do not literally translate English prepositions. Verbs that take to-infinitive in English may require a preposition or a different structure in Portuguese. Learn common collocations like lembrar de + infinitive, começar a + infinitive, tentar + infinitive (no preposition), and decidir + infinitive.

Examples:

Remember to call me -> Lembre-se de me ligar.

Try to finish -> Tente terminar.

She decided to go -> Ela decidiu ir.

Usage notes and regional preferences

Brazilian Portuguese tends to favor simpler infinitive constructions and often prefers que + subjunctive for clarity when subjects differ. The personal infinitive is less frequent in casual Brazilian speech but appears in writing and formal registers. Informal spoken Brazilian Portuguese sometimes omits pronouns or combines forms in colloquial ways; be attentive to register.

Colloquial contractions and pronoun placement

In spoken Brazilian Portuguese, direct object pronouns and clitic placement differ from European forms. For verb + infinitive combinations, pronouns may attach to infinitives in informal speech.

Examples:

Ela vai me ajudar. -> Eu vou ajudá-la is more formal; Brazilians commonly say Ela vai me ajudar or Vou te ajudar.

Practical tips for learners

– Identify the main verb and ask if the subject of the infinitive is the same; if not, consider using the personal infinitive or que + subjunctive.

– Memorize common verb + preposition patterns: aprender a, começar a, tentar + infinitive, lembrar de.

– Use the compound infinitive ter + past participle to express completion prior to the main action.

– Listen to Brazilian speech to notice when speakers choose que + subjunctive instead of an infinitive for clarity.

– When in doubt about subject differences, prefer que + subjunctive in formal contexts for safety.

Examples summarizing patterns

Intention/desire (same subject):

Eu quero aprender francês.

Different subjects with que + subjunctive:

Eu quero que ele aprenda francês.

Perception with infinitive:

Eu vi o cachorro fugir.

Permission/causation:

Minha mãe deixou eu ir à festa. -> Colloquial in Brazil.

Minha mãe permitiu que eu fosse à festa. -> More formal.

Personal infinitive to show different subject:

É importante nós estudarmos juntos.

Compound infinitive for anterior action:

Ela disse ter terminado o trabalho.

Conclusion

Mastering verb complements with the infinitivo helps you form natural Brazilian Portuguese sentences for intention, perception, obligation, permission, and more. Learn when to use the infinitivo impessoal versus the infinitivo pessoal, remember preposition patterns, and use que + subjunctive when subjects differ or formal clarity is needed. Practice by reading real sentences and listening to native speakers to internalize these patterns.