Previously it was said that every consonant can be either soft or hard. That depends on what vowel follows the consonant. Consonants followed by vowels E, Ę, Ė, I, Į, Y are pronounced softly, and consonants followed by other vowels (A, Ą, O, U, Ų, Ū) are pronounced hardly.

The letter i acts as a softening vowel. If you put i in front of A, Ą, O, U, Ų or Ū, then the consonant that is before i becomes soft.

Note that when i is before consonants A, Ą, O, U, Ų, Ū, it loses its original sound and becomes mute.

Please compare:

LA LIA
BO BIO
BU BIU
ČŪ ČIŪ

NA NIA
RO RIO
VU VIU
ZŪ ZIŪ

MA MIA
KO KIO
ŽU ŽIU
HŪ HIŪ

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