Livre, entre, autre, article, règle are examples of what I'm talking about.
I've never been sure whether I should pronounce those final two letters. When a native speaker pronounces such words, sometimes I can hear them and sometimes I can't.
Dropping liquids after consonants (e.g. in words that ends with -ble, -dre, -tre, -fle etc.) is an extremely common feature of everyday pronunciation in French (Grevisse 14th ed., §36c). Pronouncing many final schwas would be the primary reason for the recognition of these consonants and is generally considered either an affectation or a dialectal feature.
In French it's not the the
le that is left unpronounced, but the final
livre is like pronouncing
livr. Some people may actually force the last consonant and you get a sound like