Éteindre belong to the 3
rd group. Éteindre is a very common french verb.
Éteindre is conjugated the same way that verbs that end in :
-ndre
Éteindre is conjugated with
auxiliary avoir.
Éteindre verb is
direct transitive.
French verb éteindre can be conjugated in the reflexive form:
S'éteindre
Éteindre verb is a direct transitive verb, so passive voice can be used.