Infinitives are the basic form in which verbs occur and can be found in both French and English.

The French infinitive is always a single word, whereas in English the infinitive is composed of two words always beginning with “to” (to sleep, to swim, etc).

When we consider French infinitives, this is the form of the verb which is not conjugated. It’s the base form of a verb before we get into any form of conjugation, while it’s also sometimes used directly in certain sentence constructions.

In this post we’ll cover how to identify infinitives, and then get into their common uses in French grammar.

Recognizing Infinitives

French infinitive verbs come in three main forms, as well as a few irregular forms. These correspond to the three regular verb types that follow similar conjugation rules: -er, -ir, and -re verbs.

In this section we’ll introduce you to these three main French verb groups so you can start recognizing the infinitives, providing a list of examples of each type. For an introduction to French verb conjugation we recommend checking out our dedicated post.

French -er verbs

This is the most common verb form, so you’re bound to come across -er verbs all the time.

A prime example is the verb “to love”: aimer. The verb stem is “aim-”, while the infinitive ending is “-er”. To demonstrate this breakdown of the French infinitive form of aimer, let’s take a look at its conjugation in simple present tense. Note that the stem “aim-” is the base of all the conjugations.

Here are a few other -er verbs so you can start recognizing this common French infinitive:

French -re verbs

This is another common French infinitive verb form, where the verb stem is followed by -re. A classic example is the verb “to hear”: entendre. The verb stem is “entend-”, with -re as the ending of its infinitive. Take a look at the simple present conjugation of entendre and note how we base each form on the stem “entend-”.

Here are the French infinitive forms of a few other common -re verbs:

French -ir verbs

The third common infinitive form in French consists of -ir verbs. The conjugation of -ir verbs has more differences compared with that of -er and -re verbs, though for recognizing infinitives they’re just as easy.

A good example of an -ir verb is “to grow”: grandir. The stem is grand-, and its ending is -ir. We can see this in our grandir conjugation table like we saw with -er and -re verbs, though note that the plural forms have a much different ending added on to the stem.

Here are a few other common French -ir verbs in infinitive:

Irregular Infinitives

So far, all the infinitives we’ve seen in the three regular categories were pretty straightforward. Their -er, -re, and -ir endings clearly help us to identify them as infinitives, while also defining how we’ll approach their conjugation.

Even where verbs with these three common endings to their infinitives have irregular conjugations, we can therefore still generally recognize their infinitives without needing to learn the specifics of the irregular conjugations.

Some French verbs are very irregular, however, with infinitive forms that aren’t as easy to recognize. As a beginner learning French, you’ll need to just memorize these irregular French infinitives as you start studying conjugation.

Note that although these irregular infinitives generally also end with -er, -re, or -ir like their regular counterparts, they can’t be separated into stem and ending like we saw with the regular infinitives, and sometimes they’re not even pronounced the same way. Let’s see a few of the most common irregular French infinitives, along with their present indicative conjugations to demonstrate this difference:

Aller – to go: At a glance it might seem as though you’re looking at an -er verb. But nothing could be further from the truth as we can see from its conjugation:

Être – to be: Another example of deceiving appearances, this infinitive has some resemblance to an -re verb. We can’t break it down into stem and ending, however. Être is one of the most important irregular verbs in French:

Avoir – to have: This last example is somewhat reminiscent of an -ir verb in appearance, though again it’s definitely an irregular infinitive as we see through its conjugation:

Using the Infinitive on its own

There are instances when the French infinitive is used as-is without being conjugated. These are all in compound constructions, often with some other conjugated verb working alongside the infinitive, and sometimes just with a preposition or a question word. The English translation sometimes also appears as an infinitive verb with “to,” though you’ll see that the equivalent is often an -ing form of the verb.

In this section we’ll take a look at the instances where you’re most likely to encounter French infinitive verbs used in written or spoken French, with plenty of examples.

Referring to an action in the near future

In English, when you’re about to do something in a short while, you may say: “I’m going to …”

It’s the same with French. In this case the verb “aller” is conjugated, followed by the infinitive verb for the action in question.

• Nous allons visiter le zoo demain – We’re visiting the zoo tomorrow.

• Il va faire les courses la semaine prochaine – He’ll go shopping next week.

Referring to an action which has just been completed

Similarly to the previous case talking about the near future using “aller”, French has a common construction for talking about the immediate past by using “venir de …”. We conjugate the verb “venir” for the subject, we add “de”, and then add the infinitive form of the verb describing the action we’ve just done. The English translation generally uses the word “just” to describe the timing, as seen in our examples here:

• Mon frère vient d’arriver. – My brother just arrived.

• Je viens de choisir quoi porter ce soir. – I just chose what to wear tonight.

When following particular verbs

A lot of French verbs, once conjugated, are directly followed by another verb in infinitive form.

Devoir

• Tu devrais téléphoner à ton Papa dès ton arrivée à New York – You should phone your dad as soon as you arrive in New York.

Falloir

• Il faut conduire prudemment quand il neige. – It is necessary to drive carefully when it’s snowing.

Pouvoir

• Pierre peut courir plus vite que Bruno. – Pierre can run faster than Bruno.

Vouloir

• Je veux déménager à Wisconsin le printemps prochain. – I want to move to Wisconsin next spring.

When following particular verbs with prepositions

Like the previous group, many French verbs use specific prepositions followed by infinitives in order to complete their meaning. We’ll look at the prepositions à and de in this section, since they’re among the most common that follow this rule.

À

A lot of verbs take this preposition as part of their use, followed by the infinitive form of a second verb. Here’s a table of a few common French à verbs, followed by several examples showing their use with infinitives.

• À force d’étudier tous les jours, j’arrive à apprendre de plus en plus de français. – By studying every day, I manage to learn more and more French.

• Ils ont eu à travailler pendant toute la nuit – They had to work all night long.

• Il a commencé à pleuvoir. – It began to rain.

• J’ai réussi à passer mon examen de conduite. – I succeeded in passing my driving test.

De

This is another very common preposition used with specific verbs, followed by an infinitive. Check out this table of some such verbs, followed by several examples.

• J’ai accepté d’arroser leurs plantes lorsqu’ils partent en vacance. – I agreed to water their plants while they go on vacation.

• Mon chaton a arrêté de jouer quand le chien est entré – My kitten stopped playing when the dog came in.

• J’ai cessé de fumer en janvier. – I quit smoking in January.

• James et Jane ont continué d’étudier en dépit du bruit – James and Jane continued studying despite the noise.

• J’ai oublié de sortir la poubelle ce matin. – I forgot to take out the trash this morning.

• Vous risquez d’être en retard si vous ne partez pas maintenant. – You’re at risk of being late if you don’t leave now.

Other uses of the French infinitive

We’ve covered a lot of the main rules where we use the French infinitive form in written or spoken French, but this list is by no means exhaustive. Here we’ll just offer some more examples of different sentences which include infinitives so you can get an idea of the variety of contexts where they’re used.

• Mes grands-parents n’aiment pas se coucher sans boire un thé. – My grandparents don’t like going to bed without drinking a cup of tea.

• Je n’ai aucune idée quoi préparer pour mes beaux-parents. – I have no idea what to prepare for my in-laws.

• À force d’épargner, mon fils a enfin assez d’argent pour acheter une nouvelle voiture. – By saving money, my son finally has enough money to buy a new car.

• Sans réfléchir, elle s’arrêtait sur le chemin pour cueillir des framboises. – Without thinking, she stopped along the path to pick raspberries.

• Mon père essaie de quitter à 17:00, mais il finit toujours par travailler plus. – My dad tries to leave at 5pm, but he always ends up working more.

Conclusion

Infinitives are the base form of all verbs before any type of conjugation. In English you recognize infinitives since they’re always preceded by the word “to,” while in French we recognize them since they generally occur in three categories based on their endings: -er, -re, and -ir.

Infinitive French verbs are then broken down into a stem by dropping these endings, from which the conjugations are then formed. That said, of course there are also plenty of irregular French infinitives which don’t follow these rules exactly.

In a lot of situations, it’s possible to use the infinitive form directly in written or spoken French, often in combination with other verbs or prepositions. We covered plenty of examples for using infinitives, including explanations of some of the most common rules. A lot of the time the English translation of the French infinitive is with -ing verbs, while it’s also common to simply use the English infinitive with the word “to.”

Once you have a good grasp of infinitive French, you’re ready to move on to French verb conjugation. But as we saw in this post, it’s always important to first recognize the basics!