B2 · Upper Intermediate Chapter 3

Clarifying Subjects with the Personal Infinitive

5 Total Rules
50 examples
6 min
Rules in This Chapter Quick Practice

Chapter in 30 Seconds

Master the Personal Infinitive to speak with native-level precision and clarity in Portuguese.

  • Conjugate verbs to identify exactly who is performing an action.
  • Replace complex subjunctive structures with elegant infinitive forms.
  • Apply the infinitive correctly after common prepositions and time markers.
Clarify your subjects and elevate your fluency.

What You'll Learn

Hey there, language explorer! Ready to unlock a new level of precision and fluency in your Portuguese? In this chapter, we're diving deep into the Personal Infinitive (Infinitivo Pessoal) – a powerful tool that will make your speech sound incredibly natural and sophisticated. It might sound complex, but by the end, you'll wonder how you ever spoke without it! What will you learn? You'll master how to specify *exactly who* is performing an action after prepositions or impersonal expressions. Think about situations where you want to say,

For *us* to understand...
or Without *you* knowing... – the Personal Infinitive provides a direct, elegant way to do this without resorting to the often-tricky subjunctive mood. You'll learn to conjugate verbs like falar (to speak) or comer (to eat) in their personal infinitive forms to perfectly match the subject. Why does it matter? This isn't just another grammar rule; it's a key to sounding genuinely native. It allows you to express nuances and avoid ambiguity, making your Portuguese flow effortlessly. Imagine discussing plans with a friend:
Before *we* go to the cinema, we should eat dinner.
Or giving advice: "It's important for *you* to know this." The Personal Infinitive brings clarity and authenticity to these everyday interactions. How do the rules connect? We'll start by understanding the basic concept and conjugation patterns. Then, we'll explore its crucial role after various prepositions and impersonal phrases, including time expressions like antes de (before) and depois de (after). You'll see how these rules build upon each other, offering a streamlined path to subject clarification while cleverly sidestepping the subjunctive. What will you be able to do? Upon completing this chapter, you'll confidently express complex ideas with greater precision and sound far more like a native speaker. You'll navigate conversations about responsibilities, timelines, and conditions with a newfound ease, ensuring your message is always crystal clear. Ready to make your Portuguese shine? Let's go!

Learning Objectives

By the end of this chapter, you will be able to:

  1. 1
    By the end you will be able to: Conjugate and apply the personal infinitive to clarify subjects in complex sentences.

Chapter Guide

Overview

Welcome, language explorer, to a crucial step in mastering Portuguese grammar B2! This chapter introduces you to the Personal Infinitive, known in Portuguese as Infinitivo Pessoal. If you've ever found yourself struggling to precisely state *who* is doing an action in a complex sentence, especially after prepositions or impersonal phrases, this is your solution. The Personal Infinitive is a powerful and elegant grammatical construction that will significantly elevate your fluency and clarity, making your speech sound much more natural and sophisticated.
At the B2 level, moving beyond basic sentence structures is essential for expressing nuanced ideas. The Personal Infinitive allows you to do just that by providing a direct way to clarify the subject of a verb when it's dependent on another clause. Instead of relying on potentially awkward workarounds or the often-tricky subjunctive mood, you'll learn to use this unique Portuguese feature to say things like "for *us* to go" or "without *them* knowing" with ease. This isn't just about learning a new rule; it's about unlocking a key aspect of authentic Portuguese expression.
Mastering the Infinitivo Pessoal is a hallmark of advanced Portuguese grammar. It's a skill that native speakers use constantly, and integrating it into your own language will make your communication smoother, more precise, and far more understandable. By the end of this chapter, you’ll confidently apply this structure in various contexts, ensuring your message is always crystal clear and authentically Portuguese.

How This Grammar Works

The Personal Infinitive (Infinitivo Pessoal) is a fascinating and uniquely Portuguese grammatical feature that allows us to specify the subject of an infinitive verb. Unlike the impersonal infinitive (e.g., falar – to speak), the Personal Infinitive changes its ending to match the person performing the action, much like a conjugated verb. This directly addresses "The Personal Infinitive: Verbs with People Attached" and "The Personal Infinitive: Verbs with Personality (Infinitivo Pessoal)".
Let's look at the conjugation pattern for regular verbs using falar (to speak), comer (to eat), and partir (to leave):
* eu falar (for me to speak)
* tu falares (for you to speak)
* ele/ela/você falar (for him/her/you to speak)
* nós falarmos (for us to speak)
* vós falardes (for you (plural, informal) to speak)
* eles/elas/vocês falarem (for them/you (plural) to speak)
Notice how the endings change: -es, -mos, -des, -em. The first and third person singular forms are identical to the impersonal infinitive. Irregular verbs (like ser, ter, vir, pôr) will have irregular stems, but they generally follow the same personal endings. For example, ser becomes eu ser, tu seres, nós sermos, etc.
The Personal Infinitive is most commonly used after prepositions and impersonal expressions, as highlighted in "Personal Infinitive: Conjugating Verbs After Prepositions (Infinitivo Pessoal)". This is where it shines as a tool for "Avoiding the Subjunctive" when a clear subject is present.
Common triggers include:
* Prepositions: para (for/in order to), antes de (before), depois de (after), sem (without), por (by/for), ao (upon/when).
* Para eles entenderem, preciso explicar melhor. (For them to understand, I need to explain better.)
* Antes de sairmos, vamos comer. (Before we leave, let's eat.)
* Sem tu saberes, ele já fez isso. (Without you knowing, he already did that.)
* Impersonal Expressions: É importante (It's important), É preciso (It's necessary), É bom (It's good), É difícil (It's difficult).
* É importante vocês estudarem para o exame. (It's important for you (plural) to study for the exam.)
* É preciso nós falarmos sobre isso. (It's necessary for us to talk about this.)
This usage is particularly common with time expressions like antes de and depois de, as covered in "Timing & Subjects: Using Personal Infinitive (antes/depois de)". It provides a concise way to link actions to specific individuals within a temporal framework, making your B2 Portuguese sound incredibly natural and precise.

Common Mistakes

  1. 1✗ Wrong: "É importante para nós *estudar*."
✓ Correct: "É importante para nós *estudarmos*."
*Explanation:* When an impersonal expression like é importante is followed by a preposition (para) and then a specific subject (nós), the infinitive verb must be conjugated in the personal infinitive to match that subject. Here, "estudar" is the impersonal infinitive, but "estudarmos" correctly reflects the "nós" subject.
  1. 1✗ Wrong: "Antes que *nós vamos* embora, quero falar contigo."
✓ Correct: "Antes de *nós irmos* embora, quero falar contigo."
*Explanation:* While the subjunctive (que nós vamos) might seem like an option here, the Personal Infinitive is much more common and natural after prepositions like antes de when referring to a specific subject. It elegantly avoids the subjunctive mood, making the sentence smoother and more idiomatic in Portuguese grammar.
  1. 1✗ Wrong: "Ele saiu sem *tu perceber*."
✓ Correct: "Ele saiu sem *tu perceberes*."
*Explanation:* Even with irregular verbs or when the impersonal infinitive form is the same for the first and third person singular, other persons (like "tu" or "nós") still require their specific personal infinitive endings. "Perceber" is the impersonal infinitive, but "perceberes" correctly matches the "tu" subject.

Real Conversations

A

A

É importante para nós chegarmos cedo amanhã. (It's important for us to arrive early tomorrow.)
B

B

Sim, para não perdermos o início da reunião. (Yes, so we don't miss the start of the meeting.)
A

A

O que podemos fazer antes de eles partirem? (What can we do before they leave?)
B

B

Podemos jantar juntos para nos despedirmos. (We can have dinner together to say goodbye.)
A

A

Sem tu saberes, eu já comprei os bilhetes. (Without you knowing, I already bought the tickets.)
B

B

Que bom! Assim não precisamos nos preocupar com isso. (That's great! That way we don't need to worry about it.)

Quick FAQ

Q

How does the Personal Infinitive help in B2 Portuguese fluency?

It allows you to specify the subject of an infinitive verb, especially after prepositions or impersonal expressions, making your sentences more precise and sounding much more natural, often avoiding the subjunctive.

Q

Can I always use the Personal Infinitive instead of the subjunctive after prepositions?

Not always, but very often. When the subject of the infinitive is clearly stated or implied, the Personal Infinitive is usually the preferred and most natural choice, especially after prepositions like para, antes de, depois de, sem, etc., effectively "Avoiding the Subjunctive".

Q

What's the main difference between the impersonal infinitive and the Personal Infinitive in Portuguese grammar?

The impersonal infinitive (e.g., falar) refers to the action generally, without a specific subject. The Personal Infinitive (e.g., falarmos) specifies *who* is performing that action, with endings that match the subject.

Cultural Context

The Personal Infinitive is a cornerstone of advanced Portuguese grammar and is used extensively in both European and Brazilian Portuguese. Its frequent use is one of the key indicators of a highly proficient speaker. While it might feel a bit formal or clunky to English speakers initially, mastering it makes your Portuguese sound educated, precise, and effortlessly natural in everyday conversations, from making plans to giving advice. It's not just a rule; it's an ingrained part of how native speakers structure their thoughts.

Key Examples (8)

1

Obrigado por me **ajudarem** com a mudança!

Thanks for helping me with the move!

The Personal Infinitive: Verbs with People Attached
2

É impossível eles **chegarem** a tempo com este trânsito.

It's impossible for them to arrive on time with this traffic.

The Personal Infinitive: Verbs with People Attached
3

Comprei os bilhetes para nós irmos ao concerto.

I bought the tickets for us to go to the concert.

The Personal Infinitive: Verbs with Personality (Infinitivo Pessoal)
4

É melhor vocês saírem agora para não pegarem trânsito.

It's better for you all to leave now so you don't get stuck in traffic.

The Personal Infinitive: Verbs with Personality (Infinitivo Pessoal)
5

É importante nós estarmos lá às 8h.

It is important for us to be there at 8:00.

The Personal Infinitive: Avoiding the Subjunctive
6

É difícil eles entenderem o sotaque.

It's hard for them to understand the accent.

The Personal Infinitive: Avoiding the Subjunctive
7

Para vocês entenderem a piada, precisam ver o vídeo.

For you to understand the joke, you need to see the video.

Personal Infinitive: Conjugating Verbs After Prepositions (Infinitivo Pessoal)
8

Saímos sem eles perceberem.

We left without them noticing.

Personal Infinitive: Conjugating Verbs After Prepositions (Infinitivo Pessoal)

Tips & Tricks (4)

💡

Context is King

Since 1st and 3rd person singular look the same, always check the context to see who the subject is.
frontend.learn_grammar.from_rule: The Personal Infinitive: Verbs with People Attached
💡

Check the subject

If the subject of the main verb and the infinitive are different, use the personal infinitive.
frontend.learn_grammar.from_rule: The Personal Infinitive: Verbs with Personality (Infinitivo Pessoal)
💡

Check the Subject

Always check if the subject of the infinitive is different from the main verb.
frontend.learn_grammar.from_rule: The Personal Infinitive: Avoiding the Subjunctive
💡

Check the subject

Always ask: is the person doing the action the same as the main subject? If not, use the personal infinitive.
frontend.learn_grammar.from_rule: Personal Infinitive: Conjugating Verbs After Prepositions (Infinitivo Pessoal)

Key Vocabulary (6)

Infinitivo Pessoal Personal Infinitive Conjugação Conjugation Antes de Before Depois de After Ambiguidade Ambiguity Sujeito Subject

Real-World Preview

calendar

Planning a Meeting

Review Summary

  • Infinitivo + Personal Ending
  • Antes/Depois de + Personal Inf.

Common Mistakes

You mixed up the singular pronoun with a plural verb ending. Match the ending to the subject.

Wrong: Para eu comemos.
Correct: Para eu comer.

Without the subject pronoun, it's ambiguous who is arriving. Always include the pronoun if the subject changes or is not obvious.

Wrong: Antes de chegar, eu vi ele.
Correct: Antes de eu chegar, eu vi ele.

You don't need 'que' with the personal infinitive. 'Que' usually triggers the subjunctive.

Wrong: É importante que nós fazermos.
Correct: É importante nós fazermos.

Next Steps

You have done an amazing job today! Keep practicing, and you'll be speaking Portuguese with absolute confidence in no time.

Write a diary entry using 5 sentences with the personal infinitive.

Continue to: Explaining Why: Cause and Purpose

Quick Practice (10)

Fix the sentence.

Find and fix the mistake:

É bom para mim ir.

✓ Correct! ✗ Not quite. Correct answer: É bom eu ir.
Avoid 'para mim' as subject.

frontend.learn_grammar.from_rule: The Personal Infinitive: Avoiding the Subjunctive

Correct the error.

Find and fix the mistake:

Eu quero para eu comer.

✓ Correct! ✗ Not quite. Correct answer: Eu quero comer.
Same subject, use impersonal.

frontend.learn_grammar.from_rule: The Personal Infinitive: Verbs with Personality (Infinitivo Pessoal)

Fill in the blank.

É importante eles ___ (estudar) mais.

✓ Correct! ✗ Not quite. Correct answer: estudarem
Must conjugate for 'eles'.

frontend.learn_grammar.from_rule: The Personal Infinitive: Avoiding the Subjunctive

Fill in the correct form of 'falar'.

Para eles ___ (falar), precisamos de silêncio.

✓ Correct! ✗ Not quite. Correct answer: falarem
Eles requires the -em ending.

frontend.learn_grammar.from_rule: Personal Infinitive: Conjugating Verbs After Prepositions (Infinitivo Pessoal)

Correct the error in the sentence.

Find and fix the mistake:

Antes de tu sair, avisa-me.

✓ Correct! ✗ Not quite. Correct answer: Antes de tu saíres
Tu requires the -es ending.

frontend.learn_grammar.from_rule: Timing & Subjects: Using Personal Infinitive (antes/depois de)

Choose the correct form.

Para nós ___ (ir) à festa, precisamos de convite.

✓ Correct! ✗ Not quite. Correct answer: irmos
Must conjugate for 'nós'.

frontend.learn_grammar.from_rule: The Personal Infinitive: Avoiding the Subjunctive

Fill in the correct form of 'falar'.

Para eles ___ (falar), precisamos de silêncio.

✓ Correct! ✗ Not quite. Correct answer: falarem
Eles requires the -em ending.

frontend.learn_grammar.from_rule: The Personal Infinitive: Verbs with People Attached

Choose the correct sentence.

Which is correct?

✓ Correct! ✗ Not quite. Correct answer: É melhor eles irem.
Eles requires -em.

frontend.learn_grammar.from_rule: The Personal Infinitive: Verbs with Personality (Infinitivo Pessoal)

Correct the sentence.

Find and fix the mistake:

Para tu veres, eu trouxe o livro. (Correct: Para tu ___)

✓ Correct! ✗ Not quite. Correct answer: veres
Tu requires the -es ending.

frontend.learn_grammar.from_rule: Personal Infinitive: Conjugating Verbs After Prepositions (Infinitivo Pessoal)

Fill in the blank with the correct form of 'chegar' for 'eles'.

Depois de eles ___ , a festa começou.

✓ Correct! ✗ Not quite. Correct answer: chegarem
Eles requires the -em ending.

frontend.learn_grammar.from_rule: Timing & Subjects: Using Personal Infinitive (antes/depois de)

Score: /10

Common Questions (6)

It is a conjugated infinitive form used to specify the subject.
When the subject of the infinitive is different from the main verb.
It is a verb form that shows who is doing the action.
When the subject of the infinitive is different from the main verb.
It is a verb form that allows the infinitive to be conjugated for person and number.
When the subject of the infinitive is different from the main verb.
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The Versatile Past Participle
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Explaining Why: Cause and Purpose
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