Nouns ending in -ée are usually feminine.
The suffix often marks a duration or contents.
Le vent s'était calmé dans la soirée.
The wind calmed down in the evening.
Je l'ai rencontrée tard dans la soirée.
I met her late in the evening.
Vous vous êtes amusé hier à la soirée ?
Did you enjoy yourself at the party last night?
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