"Jesteśmy ludźmi."

Translation: We are people.

[OliviaSilber]

Which case is ludzmi in this sentence; intrumental?

[Jellei]

Yes.

[RiccardoRo965963]

Why do we need instrumental?

[Jellei]

Check https://www.duolingo.com/comment/16373167 - especially Part 2.

[Schkatz]

Can a group of women also say Ještemy ludžmi?

[immery]

Yes.

[uq.]

Ještemy ludžmi??

[immery]

Well they can say "Jesteśmy ludźmi"

[LightKnigh4]

We are
a band of brothers
https://www.youtube.com/watch?v=uHRWKTl_uRQ
(Pendragon is a polish band)

[Izolda_Lvovna]

Can we say 'my są ludźmi'?

[Holzhaendler]

You could say "My jesteśmy ludźmi".

"Są" is only for 3rd person plural, which is not the case here.