This is the 254th most frequent Spanish word.
nuestros
"Nuestros" means "our" (plural, masculine or mixed gender).
Indicates possession of 'amigos' (friends) belonging to the group including the speaker, showing 'nuestros' as a possessive adjective.
Nuestros amigos llegaron temprano.
Our friends arrived early.
Indicates possession of 'momentos' (moments), with 'nuestros' matching the plural masculine or mixed-gender form.
Siempre recordamos nuestros momentos felices.
We always remember our happy moments.
The word 'nuestros' identifies ownership of 'libros' (books), contrasting with another group's ownership.