What is the difference in pronunciation between
le livre rouge
les livres rouges
In this case, only the distinction between articles le (pronounced
/lə/) and les (pronounced
/lɛ/) marks the difference.
In most cases, the added s does not change the pronunciation, but sometimes a liaison between an adjective and the noun may change:
un grand espace
de grands espaces
la grande ère glacière
les grandes ères glacières
And as always, the occasional exceptions.