L'Infinitif: Overview

The infinitive (l'infinitif) is the bare, uninflected form of every French verb: parler, finir, vendre, faire, aller, être. It is the dictionary form, and it is the form French uses for an enormous range of grammatical functions that English handles with the -ing form, the to + verb construction, or simply the bare verb.

This page covers what the infinitive is, the major grammatical functions it performs, the contrast with English (where most learners' misfires originate), and the two forms it has: the infinitif présent (parler) and the infinitif passé (avoir parlé / être parti). The detailed mechanics for each function live on dedicated subpages.

The single most important takeaway, before we begin: where English uses -ing as a verbal noun ("I like swimming"), French uses the bare infinitive ("J'aime nager"). Internalising this pattern early eliminates a whole class of errors that learners otherwise make for years.

What the infinitive is

The infinitive is a non-finite form: it is not inflected for person, number, tense, or mood. It is the verb in its purest form — an action without an actor and without a time.

French infinitives end in one of three patterns, defining the three traditional verb groups:

• -er: parler, manger, aimer. The largest group — over 90% of French verbs, including all newly coined verbs (googler, liker, poster).
• -ir: finir, choisir, partir, venir, dormir. Two subgroups: regular -iss- verbs (finir) and irregular ones (partir, venir).
• -re: vendre, prendre, boire, faire, être. The smallest group, but it contains many of the most frequent verbs.

Function 1: as a noun (subject or object)

The infinitive functions as a verbal noun. This is the function that most directly clashes with English's -ing gerund.

As a subject

When an action is the subject of a sentence, French uses the bare infinitive. English uses the -ing form ("Smoking kills") or "to + verb" ("To err is human"); French simply uses the infinitive.

The main verb is third-person singular (tue, forme, demande), because an infinitive-as-subject behaves like a singular noun. A frequent variant strengthens this with c'est: Voir, c'est croire (Seeing is believing); Vouloir, c'est pouvoir (Where there's a will, there's a way). This pattern is common in proverbs and aphorisms.

As an object

The infinitive can also serve as the direct object of certain verbs, most prominently verbs of liking, preference, and modality. Here too, English uses -ing or "to + verb"; French uses the bare infinitive.

The most common verbs taking an infinitive directly (no preposition) are: aimer, adorer, détester, préférer, vouloir, pouvoir, devoir, savoir (= know how to), oser, espérer, sembler, paraître. These verbs link directly to a following infinitive without any connecting word.

Function 2: after most prepositions

French uses the infinitive after almost every preposition. This is a deep structural difference from English, where prepositions take the -ing form ("before leaving," "without eating," "for being late"). In French, those same prepositions take the infinitive.

There is one major exception to this rule: the preposition en takes the gérondif form (en + V-ant), not the infinitive. En partant (while leaving / on leaving), not en partir. This is the only systematic exception. Every other preposition — à, de, pour, sans, avant de, après, au lieu de, afin de, par, dans, sur — takes the infinitive.

A small but important wrinkle: avant and afin require de before the infinitive (avant de partir, afin de réussir), while pour and sans take the infinitive directly (pour réussir, sans manger). And après takes a special compound form, the infinitif passé, discussed below.

For the full discussion of which preposition takes which form (and the famously arbitrary choice of à vs. de after specific verbs), see the dedicated Infinitive after Prepositions page.

Function 3: with modal and aspectual verbs

Modal verbs (pouvoir, devoir, vouloir, savoir) and aspectual verbs (commencer à, finir de, continuer à, arrêter de) chain to a following infinitive. This pattern is fully equivalent to English "can + verb," "must + verb," "want to + verb."

The modal+infinitive pattern is high-frequency: every conversation in French is full of these chains. They are also a frequent same-subject construction — the subject of the modal is the same as the implicit subject of the infinitive. Je veux partir means I want and I leave. If you want a different subject for the second action, you must move to a que-clause with the subjunctive (Je veux que tu partes — I want you to leave). See the Subjunctive Overview for that pivot.

Function 4: as impersonal command (signs, instructions, recipes)

French uses the bare infinitive for impersonal commands — instructions that are not addressed to any specific person but to anyone reading. Public signs, recipes, procedural manuals, and forms all favour the infinitive over the imperative.

The logic: an imperative (ne fumez pas, tirez) addresses a specific person — vous. An infinitive (ne pas fumer, tirer) addresses no one in particular; it is a universal directive. French has crystallised this distinction into a register choice: addressed → imperative; impersonal → infinitive.

Note how negation works in this construction: ne pas sits together before the infinitive, in that order. Ne pas fumer, Ne pas dépasser cette ligne, Ne pas se pencher au dehors. This is different from finite-verb negation, where ne and pas wrap the verb (Je ne fume pas).

A specific subcase: French recipes use the infinitive throughout. Each step is a bare infinitive — Mélanger les œufs, Ajouter la farine, Faire cuire 30 minutes, Laisser refroidir. This convention is so strong that recipes written with vous imperatives sound oddly informal. For the detailed treatment, see The Infinitive in Instructions and Recipes.

Function 5: idiomatic and structural uses

A few additional constructions deserve a quick mention.

After il faut (general directive, no specific addressee):

When il faut addresses a specific person, it switches to a que-clause with the subjunctive (il faut que tu manges).

After verbs of perception (voir, entendre, sentir, écouter, regarder) — French uses only the infinitive, never a participle:

Causative faire and permissive laisser — faire + infinitive means "to have someone do" or "to make someone do":

See the dedicated Causative Faire page for the full treatment.

The two infinitive forms

French infinitives come in two tenses: présent and passé.

The infinitif présent is the basic form covered throughout this page (parler, finir, vendre). It expresses an action with no specific time reference; the main verb's tense anchors the timeline. Avant de partir, j'ai fermé la porte refers to a past leaving because ai fermé sets the reference point.

The infinitif passé is the compound form: avoir or être (in the infinitive) + past participle. Avoir parlé, être parti, s'être levé. It expresses an action completed before the main verb's action.

The infinitif passé is essential for après + infinitif passé, which translates English "after + V-ing." The simple infinitive does not work: après partir is wrong; you must say après être parti. Auxiliary selection follows passé composé rules. For the full mechanics, see the Infinitive Passé page.

The English-speaker trap: -ing is not infinitive

The single most common error English speakers make with French infinitives is reaching for the -ing form (the participe présent or the gérondif) where French requires the infinitive. The trap occurs in three predictable places:

Trap 1: Verbal noun as subject.

Trap 2: After "like / hate / prefer."

Trap 3: After prepositions.

The mental rewrite: when English uses -ing as a verbal noun (subject, object, or after a preposition), French uses the infinitive. The single exception is the preposition en, which takes the gérondif (en + V-ant), the closest French gets to a true -ing form.

Pronouns and the infinitive

When a verb in the infinitive takes a pronoun object, the pronoun precedes the infinitive itself (not the main verb).

Whenever a clitic pronoun (me, te, se, le, la, lui, leur, y, en, nous, vous, les) is the object of an infinitive, it sits immediately before that infinitive. In the infinitif passé, the pronoun goes between the auxiliary and the past participle: avoir vu → l'avoir vu (having seen him).

Common Mistakes

Mistake 1: Translating English -ing as the participe présent.

Mistake 2: Adding to (or de) where French wants a bare infinitive.

Mistake 3: Using a finite clause where French uses an infinitive (same subject).

Mistake 4: Misplacing the pronoun with an infinitive.

Mistake 5: Negation of an infinitive — wrapping instead of stacking.

Key takeaways

• The infinitive is the bare, uninflected form of the verb (parler, finir, vendre). It is the dictionary form and the most syntactically flexible verb form in French.
• French uses the bare infinitive, not the -ing form, where English uses -ing as a verbal noun: as subject (Fumer tue), as object of a verb (j'aime lire), and after most prepositions (avant de partir, sans manger).
• The single exception is the preposition en, which takes the gérondif (en partant).
• Modal and aspectual verbs (pouvoir, devoir, vouloir, commencer à, finir de) chain directly to a following infinitive when the subject is the same. Different subjects require a que-clause with the subjunctive.
• The infinitive serves as the standard form for impersonal commands: signs (Ne pas fumer), recipes (Mélanger les œufs), procedures (Cocher la case).
• French has two infinitive tenses: infinitif présent (parler) and infinitif passé (avoir parlé, être parti). The compound form expresses anteriority — completed action before the main verb.
• Pronouns precede the infinitive they govern: le faire, te parler, lui téléphoner. In the infinitif passé, they sit between the auxiliary and the past participle: l'avoir vu.
• Negation of an infinitive uses ne pas together before the verb: Ne pas fumer, not Ne fumer pas.
• The single most reliable conversion rule for English speakers: when in doubt, replace English -ing (as verbal noun) with a French infinitive. The exceptions are limited and learnable.