The most common and irregular verbs of French

The verbs we deal with on this page are generally the most common and most irregular verbs of French. On the following pages, we will deal with other irregular French verbs which in general share a lot in common and are actually less "irregular" than the verbs listed on this page.

être, avoir, aller, faire

These verbs are extremely common¹ and highly irregular in a number of respects:

They have more distinct present tense forms than other verbs. In particular, they don't follow the usual pattern of all present tense singular forms sounding the same.
Their 3rd person plural present tense form ends in -ont, unlike any other verb in the language.
They have either present tense forms or future stems (or both) that are wildly different from the infinitive (sometimes clearly derived from different roots).
In the case of faire and être, along with dire, their vous forms are the only ones in the language not to end in -ez.
They have irregular subjunctive forms.

The table below lists the irregular features of each of the four verbs. Some of this information is aimed at advanced learners. Beginners are advised to click on the verb to see its conjugation, and look at the present tense. Intermediate learners will want to look at the other tenses.

Verb	Meaning	Irregularities
être	(to) be	5/6² distinct present tense forms, of which suis, sommes and sont bear no relation to the infinitive; sommes is the only nous form in the language not to end in -ons; êtes one of two vous forms in the language not to end in -ez; future forms ser-, derived from Latin ESSE, different from the infinitive, derived from Latin STARE (cf. Spanish ser vs estar); stem of the imperfect and present participle (étais etc) is not that of the nous form of the present tense (virtually the only such form in the language³); subjunctive forms not predictably based on the 3rd person plural of the present tense; nous and vous subjunctive forms do not have -i- (soyons, soyez); singular endings -s/-s/-t rather than -e/-es/-e; past participle été one of very few to end in -é but not be from a regular -er verb.
avoir	(to) have	1st person singular present tense form ai different to other singular forms as/a; singular present tense forms do not end in -s/-s/-t in the spelling; 3rd person plural form ont; future stem aur- a phonetic contraction of previous form avrai etc (cf Spanish habré); present participle ayant has a different stem to the nous form avons; subjunctive forms not based on the 3rd person plural of the present tense; nous and vous subjunctive forms do not have -i- (ayons, ayez); singular forms aie/aies/ait do not follow the normal subjunctive ending pattern (-e/-es/e); unpredictable past participle eu.
aller	(to) go	Initial v- of present tense forms not present in the infinitive; 3rd person plural form vont one of only four to end in -ont; Past participle allé one of very few to end in -é but not be from a regular -er verb; Irregular subjunctive form aille etc not based on the 3rd person plural present tense form; Future stem ir- derived from a different root to the infinitive, the original Latin infinitive IRE. (The source of the all- forms is not generally agreed upon.)
faire	(to) make, do	Present tense vous form faites one of only two (with êtes) not to end in -ez; Reduction of the vowel to a schwa in the pronunciation of faisons, faisais etc, as well as in the future stem fer-; Irregular subjunctive form fasse, not based on the 3rd person plural present tense form, plus fassions/fassiez, which do not resemble the imperfect forms; Past participle fait practically the only one to end in -ait⁴.

The modal auxiliaries pouvoir, vouloir and savoir

After the four verbs in the previous section, these verbs are arguably the next most irregular, since they have unpredictable subjunctive forms and future stems. The short past participles of pouvoir and savoir are also unusual.

Verb	Engliah meaning	Future stem	Subjunctive form	Past participle	Other irregularities
pouvoir	(to) be able to	pourr-	je puisse nous puissions	pu	Singular present tense form je/tu peux spelt with -x rather than -s. Present tense form je puis retained in literary usage and in the inverted form puis-je.
vouloir	(to) want (to)	voudr-	je veuille nous voulions veuillez⁵	voulu	Singular present tense form je/tu veux spelt with -x rather than -s.
savoir	(to) know (how to)	saur-	je sache nous sachions sachez⁵	su	Present participle sachant.

Other features of these verbs' conjugations, such as the vowel alternation in je veux vs vous voulez, occur in other irregular verb patterns too (cf je meurs vs vous mourez).

Where to go next...

Irregular verb patterns in French shows the main patterns of other irregular verbs in French.
How to conjugate irregular French verbs shows how to combine general rules of French verb formation with specific features of particular irregular verbs to give the different tense forms and participles.

Notes:
1. These are common, key verbs in the language partly because they have auxiliary uses:

avoir and être are used to form compound tenses (similar to English I have done), and être to form the passive (similar to English the postman was bitten by the dog);
aller is used to form a type of immediate future construction (similar to English I'm going to do it);
faire is used to form a causative construction (similar to English I'll have the car repaired; I'll make him do it: see this site's article on the translation of the keyword 'faire').

2. Six forms in the written language: suis, es, est, sommes, êtes, sont. In the spoken language, most speakers do not make a discriminatory pronunciation difference between es and est.
3. To my knowledge, the only other "irregular" imperfect/present participle stem still encountered in contemporary French is the slightly archaic florissait from fleurir. The verb falloir has fallait, arguably predictable from the infinitive, and pleuvoir has pleuvait, but arguably an "artificial" nous form pleuvons (and certainly a plural form pleuvent) are possible.
4. The verb traire (to milk) has trait.
5. The forms veuillez and sachez are used as a type of imperative to mean 'kindly ...' and 'you should know that ...', 'please acknowledge that ...' respectively.

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