How to Conjugate French -IR Verbs

Once you’re comfortable with -er verbs, the next pattern worth mastering is the second regular group: verbs like finir (to finish), choisir (to choose), réussir (to succeed), and grandir (to grow up). These are often called “second group” verbs, and they share a distinctive feature you won’t find anywhere else in French: an extra -iss- that shows up in some forms and not others. Learn that one quirk and the whole family falls into place.

The core pattern

Take the stem of finir — drop the -ir and you get fin-. Present tense conjugates like this:

• je finis
• tu finis
• il/elle finit
• nous finissons
• vous finissez
• ils/elles finissent

Notice what’s happening: je, tu, il stay short — just the stem plus -is, -is, -it. But nous, vous, ils insert -iss- before the ending: finiss-ons, finiss-ez, finiss-ent. That’s the signature of this whole verb family, and it’s why grammar books sometimes call these “-issons verbs.” Once you can hear that split — short in the singular, -iss- in the plural — you can conjugate choisir, réussir, grandir, remplir, and dozens of others the same way.

Building other tenses

The -iss- doesn’t disappear once you leave the present tense — it carries forward into two more tenses built on the same stem:

• Imparfait keeps -iss- all the way through: je finissais, tu finissais, il finissait, nous finissions, vous finissiez, ils finissaient. Unlike the present, there’s no short/long split here — every form gets the -iss-.
• Subjonctif présent works the same way: que je finisse, que tu finisses, qu’il finisse, que nous finissions, que vous finissiez, qu’ils finissent.

Two tenses break from the fin- stem entirely and use the whole infinitive as their base instead:

• Futur simple: finir + -ai, -as, -a, -ons, -ez, -ont → je finirai, tu finiras, il finira, nous finirons, vous finirez, ils finiront.
• Conditionnel: finir + -ais, -ais, -ait, -ions, -iez, -aient → je finirais, tu finirais, il finirait, nous finirions, vous finiriez, ils finiraient.

And for compound tenses like passé composé, these verbs use avoir plus a past participle ending in -i: j’ai fini, tu as choisi, elle a réussi. No -iss-, no surprises — just drop the -ir and add -i.

Not every -ir verb works this way

Here’s the catch, and it’s worth taking seriously: ending in -ir does not guarantee a verb follows the -issons pattern. French has at least two other major -ir families that conjugate completely differently.

• Verbs like partir, sortir, dormir, sentir, and servir drop a consonant from the stem instead of adding -iss-: it’s je pars, je dors, je sens — not “je parisse” or “je dorissons.” The nous/vous forms don’t get an -iss- either.
• Verbs like venir and tenir follow their own irregular pattern entirely: je viens, tu tiens, but nous venons, nous tenons — a stem change that has nothing to do with -iss-.

So when you meet a new -ir verb, don’t assume — check it. That’s really the only reliable method: the infinitive ending alone doesn’t tell you which family a verb belongs to.

Practice it

The best way to internalize the -iss- split is to drill it until it’s automatic. Head to the Verbs & Tenses page, select finir, choisir, réussir, and a few other second-group verbs alongside présent, imparfait, and subjonctif, and then jump into the flashcard practice to build the reflex. Once nous finissons stops requiring a mental pause, you’re ready to add futur and conditionnel into the mix.