Avoir auxiliary

Avoir in composed tenses

There are only two auxiliaries in French: avoir and être.
Avoir is mainly used in composed tenses: j'ai mangé, il aurait su...
To build present perfect or past, you have to take the avoir auxiliary and add verb past participle.

Avoir, for action verbs

Avoir is used to conjugate verbs which express an action. For state verbs, you have to use the other auxiliary être.

Even if the large majority of verbs are action verbs, most of them can be conjugated with the two auxiliaries. Of course, there meaning is changing...

With avoir, verbs express an action meanwhile they express the result of this action with être.

aborder     crever    expirer
descendre   changer   enlaidir
rajeunir    vieillir  maigrir
...

Eg: J'ai descendu le piano.
Je suis descendu.

This list is not complete and there are lots of verbs of this kind.

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