This is the 1828th most frequent French word.
fiers
"Fiers" means "proud" (plural form).
Here, 'fiers' is used as an adjective, agreeing in gender and number with the plural subject 'Nous' which refers to the speaker and others.
Nous sommes fiers de vos réalisations.
We are proud of your achievements.
In this sentence, 'fiers' is an adjective modifying 'ils', agreeing in gender (masculine) and number (plural).
Ils étaient très fiers de leur travail.
They were very proud of their work.
The adjective 'fiers' complements the subject 'Vous', indicating a plural form (formal or plural 'you') and conveying pride in oneself.