How to Use the French Conditional Mood

The French conditional (le conditionnel) mood is very similar to the English conditional mood. It describes events that are not guaranteed to occur, those that are often dependent on certain conditions. While the French conditional mood has a full set of conjugations, the English equivalent is simply the modal verb "would" plus the main verb.

Le Conditionnel: If...then

The French conditional is mainly used in if...then constructs. It expresses the idea that if this were to happen, then that would be the result. 

While French uses the word si in the "if" or condition clause, it does not use a term for "then" in the result clause. The conditional verb itself is used in the result (then) clause, while only four other tenses are permitted in the si clause: présent, passé composé, imparfait, and plus-que-parfait.

• Il mangerait s'il avait faim: He would eat if he were hungry
• Si nous étudiions, nous serions plus intelligents: If we studied, (then) we would be smarter
• Il mangerait avec nous si nous l'invitions: He would eat with us if we invited him

Special Cases: Vouloir and Aimer

The verb vouloir (to want) is used in the conditional to express a polite request:

• Je voudrais une pomme: I would like an apple
• Je voudrais y aller avec vous: I would like to go with you

However, you can't say "si vous voudriez" to mean "if you would like," because the French conditional can never be used after si.

The verb aimer (to like, love) is used to express a polite desire, sometimes one that cannot be fulfilled:

• J'aimerais bien le voir: I would really like to see it
• J'aimerais y aller, mais je dois travailler: I would like to go, but I have to work

Conjugating le Conditionnel

Conjugating the conditional may be one of the simplest French conjugations you'll encounter. There is only one set of endings for all verbs. Most of them — even many that are irregular in the present tense — use their infinitives as the root. There are only about two dozen stem-changing or irregular verbs that have irregular conditional stems but take the same endings.

To show you how easy conditional conjugations are, let's take a look at how it applies to different types of verbs. We'll use jouer (to play) as our regular -er example, finir (to finish) as our irregular -ir example, and dire (to say) as one exception to the rules.

Subject	Ending	Jouer	Finir	Dire
je	-ais	jouerais	finirais	dirais
tu	-ais	jouerais	finirais	dirais
il	-ait	jouerait	finirait	dirait
nous	-irons	jouerions	finirions	dirions
vous	-iez	joueriez	finiriez	diriez
ils	-aient	joueraient	finiraient	diraient

Notice how we had to drop the "e" in dire before adding the conditional endings. This is the sort of change you will find in that handful of verbs that do not follow the standard conditional conjugation pattern. Other than that, you can see how easy it is to form the conditional from almost any verb, even the irregular ones.

The Verbs That Don't Follow the Rules

So which verbs are you going to have to pay attention to when it comes to the conditional verb mood? Dire and other verbs that end in -ire are easy compared to some of the others, a few barely resemble the infinitive form while others take on more subtle changes. 

The following verbs are irregular in the conditional mood. Notice how the stems change and that they do not use the infinitive form like the other verbs do. There are two rules here:

1. The conditional stem always ends in "r." 
2. The exact same verbs are irregular in the future tense and use the same stems.

When conjugating these into the conditional, simply attach the endings noted above according to the subject pronoun in your sentence.

Infinitive Verb	Conditional Stem	Similar Verbs
acheter	achèter-	achever, amener, emmener, lever, promener
acquérir	acquerr-	conquérir, s'enquérir
appeler	appeller-	épeler, rappeler, renouveler
aller	ir-
avoir	aur-
courir	courr-	concourir, discourir, parcourir
devoir	devr-
envoyer	enverr-
essayer	essaier-	balayer, effrayer, payer
essuyer	essuier-	appuyer, ennuyer
être	ser-
faire	fer-
falloir	faudr-
jeter	jetter-	feuilleter, hoqueter, projeter, rejeter
nettoyer	nettoier	employer, noyer, tutoyer, -ayer stem-changing verbs
pleuvoir	pleuvr-
pouvoir	pourr-
savoir	saur-
tenir	tiendr-	maintenir, obtenir, soutenir
valoir	vaudr-
venir	viendr-	devenir, parvenir, revenir
voir	verr-	revoir
vouloir	voudr-