Raffermir belong to the 2
nd group.
Raffermir is conjugated the same way that verbs that end in :
-ir
Raffermir is conjugated with
auxiliary avoir.
Raffermir verb is
direct transitive.
French verb raffermir can be conjugated in the reflexive form:
Se raffermir
Raffermir verb is a direct transitive verb, so passive voice can be used.