F ----- Feminine
Sing. - Singular
Plu. -- Plural
vow. -- vowel
cons -- consonent
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Examples :
il libro (the book) ------------- i libri (the books)
l'uomo (the man) ---------------- gli uomini (the men)
lo zio (the uncle) -------------- gli zii (the uncles)
lo scopo (the aim) -------------- gli scopi (the aims)
l'inno (the hymn) --------------- gl'inni (the hymns)