Auxiliary verbs are used to form compound tenses and several verbal periphrases by combining with a non-finite form of the main verb. The main auxiliary verbs are être and avoir, and the choice of auxiliary often depends on the verb type, its transitivity or its pronominal use. They are essential for forming structures like the passé composé, the plus-que-parfait, the futur antérieur, the futur proche and the passive voice. Mastery also requires knowing the past participle, the verbal infinitive and the agreement of the past participle, as in Past Participle Agreement.},{

Have is the most frequent auxiliary and is used mainly with many transitive verbs to form compound tenses. Its auxiliary value is recognizable in forms like I’ve, you have, he has, we have and they have, which precede a past participle. It also appears in certain periphrases, notably with modal verbs already studied in Modal Verbs.

SujetSubject	VerbeVerb	ExempleExample
JeI	j’aiI have	J’ai parlé quand la séance a commencéI have spoken when the session began
TuYou	tu asyou have	Tu as fini quand le travail était prêtYou have finished when the work was ready
IlHe	il ahe has	Il a pris le train quand la gare a ouvertHe has taken the train when the station opened
NousWe	nous avonswe have	Nous avons eu faim quand le dîner a tardéWe were hungry when dinner was late
IlsThey	ils ontthey have	Ils ont fait le trajet quand la route était libreThey have made the trip when the road was clear

Be serves as an auxiliary with pronominal verbs, with a portion of movement verbs, and with the passive voice. It appears in forms such as I am, you are, he is, we are and they are, followed by a past participle or another non-finite form depending on the construction. The link between be and pronominal verbs is central in [Pronominal Verbs], where the auxiliary accompanies the reflexive pronoun.

SujetSubject	VerbeVerb	ExempleExample
JeI	je suisI am	Je suis allé tôt quand le magasin a ferméI went up early when the store closed
TuYou	tu esyou are	Tu es venu vite quand l’appel a sonnéYou came quickly when the call rang
IlHe	il esthe is	Il est monté au troisième étage quand l’ascenseur a arrêtéHe went up to the third floor when the elevator stopped
NousWe	nous sommeswe are	Nous sommes partis ensemble quand la pluie a cesséWe left together when the rain stopped
EllesThey	elles sontthey are	Elles sont levées tôt quand le réveil a sonnéThey got up early when the alarm rang

The present perfect is formed with the auxiliary conjugated in the present and the past participle of the main verb. With avoir, it often expresses a completed action; with être, it appears especially with pronominal verbs and several movement verbs. The basics of the past participle are detailed in Past Participle, and the form of the auxiliary then determines any agreement.

IdéeIdea	ExempleExample
Le passé composé associe un auxiliaire au présent et un participe passé.The present perfect combines an auxiliary in the present and a past participle.	J’ai parlé quand la réunion a commencé.I have spoken when the meeting began.
Avec avoir, le participe passé suit l’auxiliaire.With avoir, the past participle follows the auxiliary.	Nous avons fini quand le film a cessé.We have finished when the movie ended.
Avec être, le participe passé suit l’auxiliaire et peut s’accorder.With être, the past participle follows the auxiliary and may agree.	Elle est arrivée quand la porte a ouvert.She arrived when the door opened.

The pluperfect is formed with the auxiliary in the imperfect followed by the past participle. It places an action anterior to another past action and keeps the same logic of auxiliary choice as the passé composé. This structure often appears in narratives or explanations of anteriority.

IdéeIdea	ExempleExample
Le plus que parfait marque une action antérieure dans le passé.The pluperfect marks an earlier action in the past.	J’avais parlé quand le professeur est entré.I had spoken when the professor entered.
Avec être, l’auxiliaire est aussi à l’imparfait.With être, the auxiliary is also in the imperfect.	Nous étions partis quand la pluie a commencé.We had left when the rain began.
Avec avoir, l’auxiliaire garde la valeur d’antériorité.With avoir, the auxiliary maintains the anteriority value.	Ils avaient pris le bus quand la grève a été annoncée.They had taken the bus when the strike was announced.

The future perfect is formed with the auxiliary in the simple future followed by the past participle. It expresses that an action will be completed before a future moment or before another future action. This form belongs to compound tenses and rests on the same system as the present perfect and the pluperfect.

IdéeIdea	ExempleExample
Le futur antérieur présente une action achevée dans l’avenir.The future perfect presents a completed action in the future.	J’aurai parlé quand tu arriveras.I will have spoken when you arrive.
Avec être, l’auxiliaire passe au futur.With être, the auxiliary moves to the future.	Elle sera sortie quand la réunion commencera.She will have left when the meeting starts.
Avec avoir, l’auxiliaire garde sa fonction de support.With avoir, the auxiliary keeps its supporting function.	Nous aurons fait le travail quand le soir viendra.We will have done the work when evening comes.

Pronominal verbs use être as auxiliary in compound tenses, because the verb is used with a reflexive pronoun that is part of its structure. The compound form therefore follows the reflexive pronoun plus être conjugated plus past participle. Their behavior is studied in detail with Pronominal Verbs.

SujetSubject	VerbeVerb	ExempleExample
JeI	me suis levéI got up	Je me suis levé quand l’alarme a sonné.I got up when the alarm rang.
TuYou	t’es lavéyou washed yourself	Tu t’es lavé quand la journée a commencé.You washed yourself when the day began.
ElleShe	s’est habilléeshe dressed herself	Elle s’est habillée quand la porte a frappé.She dressed herself when the door knocked.
NousWe	nous sommes rencontréswe met	Nous nous sommes rencontrés quand la classe a fini.We met when the class finished.
IlsThey	se sont cachésthey hid	Ils se sont cachés quand le bruit a monté.They hid when the noise rose.

Several movement verbs take être or avoir depending on their transitivity and sense. When the verb is intransitive, être is common in compound tenses; when it is transitive, avoir may again become the auxiliary. Verbs like monter, sortir and passer illustrate this change of value, which depends on the meaning and the presence of a direct object.

IdéeIdea	ExempleExample
Monter peut prendre être quand le verbe exprime un déplacement.Monter can take être when the verb expresses movement.	Il est monté quand l’ascenseur a cessé.He went up when the elevator stopped.
Monter peut prendre avoir quand le verbe est transitif.Monter can take avoir when the verb is transitive.	Il a monté la valise quand le train a démarré.He lifted the suitcase when the train started.
Sortir change aussi selon le sens et la transitivité.Sortir also changes depending on meaning and transitivity.	Elle est sortie quand la pluie a arrêté.She went out when the rain stopped.
Passer peut changer d’auxiliaire selon l’emploi.Passer can change the auxiliary depending on usage.	Nous avons passé la frontière quand le contrôle a ouvert.We crossed the border when the checkpoint opened.

Non-finite forms serve as the basis for several verbal constructions and do not carry the grammatical person like a conjugated verb. The infinitive names the action, the present participle often marks simultaneity, the past participle is used to form compound tenses and the gerund is formed with en plus the present participle. These forms are closely linked to the [Verbal Infinitive] and to the past participle system.

IdéeIdea	ExempleExample
L’infinitif est la forme de base du verbe.The infinitive is the base form of the verb.	Parler quand il faut écouter.Speak when you must listen.
Le participe présent exprime une action en cours ou liée au contexte.The present participle expresses an action in progress or related to the context.	Parlant doucement quand la salle dormait.Speaking softly when the room was asleep.
Le participe passé sert à construire les temps composés.The past participle is used to build compound tenses.	Fini quand le signal a retenti.Finished when the signal sounded.
Le gérondif se forme avec en et le participe présent.The gerund is formed with en and the present participle.	En parlant quand nous marchions, tout devenait clair.While speaking when we were walking, everything became clear.

Several very common verbs have irregular past participles that must be recognized quickly. The essential forms are été for être, eu for avoir, allé for aller, fait for faire and pris for prendre. These forms appear irregularly and must be memorized with the compound tenses.

VerbeVerb	ParticipeParticiple	ExempleExample
êtreto be	étébeen	Il a été là quand la porte s’est ouverte.He was there when the door opened.
avoirto have	euhad	Nous avons eu du temps quand la pluie est tombée.We had time when the rain fell.
allerto go	allégone	Elle est allée vite quand le train a freiné.She went quickly when the train slowed.
faireto do	faitdone	J’ai fait le gâteau quand la cuisine était calme.I made the cake when the kitchen was calm.
prendreto take	pristaken	Ils ont pris le chemin quand le soleil est revenu.They took the path when the sun came back.

Regular verbs maintain stable patterns that help form compound tenses and recognize the past participle. Verbs ending in -er typically yield a past participle ending in -é, -ir verbs like finir typically yield a past participle ending in -i, and several -re verbs typically yield a past participle ending in -u. These regularities are also seen in the base forms taught in [Verb Groups] and in [Regular Verbs].

SujetSubject	VerbeVerb	ExempleExample
ParlerSpeak	parle et parlonsspeak and let's speak	Parler quand nous parlons.Speak when we speak.
FinirFinish	finis et finissonsfinish and let's finish	Finir quand nous finissons.Finish when we finish.
PrendreTake	prends et prenonstake and let's take	Prendre quand nous prenons.Take when we take.

Compound tenses and verbal periphrases rely on combining an auxiliary with a non-finite form, but their interpretation depends on the tense, the meaning and the register. The near future with aller plus infinitive is very common in speech, while compound tenses mark anteriority or completion in more varied contexts. With the passive voice, être carries the grammatical structure while the past participle expresses the action suffered.

IdéeIdea	ExempleExample
Le futur proche emploie aller plus infinitif.The near future uses aller plus infinitive.	Je vais parler quand tu seras prêt.I am going to speak when you are ready.
Le passé récent emploie venir de plus infinitif.The recent past is formed with venir de plus infinitive.	Il vient de finir quand la cloche a sonné.He has just finished when the bell rang.
La voix passive emploie être plus participe passé.The passive voice uses être plus past participle.	La porte est fermée quand la nuit tombe.The door is closed when night falls.

The first auxiliaries to recognize are être and avoir, as they structure the majority of compound tenses. The first irregular past participles to memorize are été, eu, allé, fait and pris, as they appear very early in reading and production. Once these forms are mastered, learners can identify more quickly the most common compound tenses and periphrases, including those used in [Present Perfect], [Pluperfect], and [Future Perfect].