Warenkorb

"La" → Lo? But "La" is feminine article, "El" is masculine. Maybe the user just wants three forms regardless of gender? Maybe they are okay with that.

"Redes de Computadoras" as a proper noun in the title is skipped but the other "redes de computadoras" is replaced again.

Also, the user mentioned "skip proper nouns," so I have to make sure names like "Tanenbaum" and acronyms like TCP/IP remain unchanged. I'll go through each line carefully, replacing terms where appropriate and ignoring the rest.