This is the 592nd most frequent French word.
supplémentaires
"Additional" or "extra."
The word 'supplémentaires' in this sentence modifies 'documents,' indicating that additional or extra documents are needed beyond what is already considered.
J'ai besoin de documents supplémentaires pour le projet.
I need additional documents for the project.
Here, 'supplémentaires' describes 'chaises,' suggesting that more chairs were acquired to accommodate a specific need.
Nous avons commandé des chaises supplémentaires pour l'événement.
We ordered extra chairs for the event.
In this context, 'supplémentaires' refers to 'cours,' implying that extra classes beyond the regular schedule are being provided.