L’infinitif – How to use infinitive verb form in French

Key takeaways

• The infinitive (l’infinitif) is the basic, unconjugated verb form.
• French infinitives end in -er, -ir, or -re (parler, finir, vendre).
• It can function as a noun, follow another verb, or express purpose.
• Common in fixed expressions (il faut manger, avant de partir).
• Essential for building vocabulary and recognizing verb families.

What Is an Infinitive in French?

The infinitive (l’infinitif) is the neutral, unconjugated form of a verb. It’s the form you find in dictionaries.

Examples:

• parler → to speak
• finir → to finish
• aller → to go

Forms of the French Infinitive

French verbs fall into three main groups:

1. -er verbs (regular): parler, aimer, jouer
2. -ir verbs (regular): finir, choisir, réussir
3. -re verbs (regular/irregular): vendre, attendre, prendre

Some verbs are irregular but still use an infinitive base: avoir, être, aller, faire.

How to Use the Infinitive in French

1. As a Noun

• Fumer est interdit. → Smoking is forbidden.
• Lire est agréable. → Reading is enjoyable.

2. After Certain Verbs

Some verbs are directly followed by an infinitive:

• Je veux manger. → I want to eat.
• Nous aimons voyager. → We like to travel.

3. With Prepositions

• Avant de partir, ferme la porte. → Before leaving, close the door.
• Sans dire un mot, il est parti. → Without saying a word, he left.

4. In Fixed Expressions

• Il faut étudier. → One must study.
• C’est difficile à comprendre. → It’s hard to understand.

The Infinitive vs Conjugated Verbs

The infinitive expresses the general action, while conjugated verbs mark person, tense, and mood.

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Examples of Infinitives in Sentences

• Apprendre une langue est enrichissant. → Learning a language is rewarding.
• Elle préfère rester à la maison. → She prefers to stay home.
• Il a oublié de répondre au message. → He forgot to reply to the message.
• Nous allons partir demain. → We are going to leave tomorrow.

Common Mistakes

• Using a conjugated verb after vouloir or pouvoir instead of infinitive.
• Forgetting de or à when required before the infinitive.
• Confusing infinitive forms (parler vs parlé – present vs past participle).

Exercises: Practice with the Infinitive

1. Fill in the blanks

• Je veux ________ (aller) au cinéma.
• Elle a oublié de ________ (fermer) la porte.
• ________ (lire) est amusant.

2. Translate into French

• He likes to swim.
• Before leaving, I said goodbye.
• Smoking is dangerous.

3. Correct the mistakes

• ❌ Nous aimons jouons au foot.
• ❌ Il préfère parle anglais.

Answers

1. aller | fermer | Lire
2. Il aime nager | Avant de partir, j’ai dit au revoir | Fumer est dangereux
3. Nous aimons jouer au foot | Il préfère parler anglais

Tips for Mastering the Infinitive

• Always learn new verbs with their infinitive form.
• Practice recognizing verb families (-er, -ir, -re).
• Pay attention to verbs that require à or de before the infinitive.
• Try building sentences with vouloir, pouvoir, devoir + infinitive.

For further learning, check our French verb tenses overview. For strategies, see learning French effectively. And to plan your journey, explore how long it takes to learn French fluently.

Summary

The French infinitive (l’infinitif) is the base form of verbs, used as a noun, after other verbs, with prepositions, and in fixed expressions.

Resources like Lingoculture’s French Infinitive and Study.com’s guide on using infinitive verbs in French provide deeper insights. With practice, you’ll easily recognize and use infinitives like parler, finir, vendre, aller, être while you learn French with Promova