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 hard.)

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 before these consonants the softening vowel i is not pronounced.

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
labas and Aliaska
nors and aštuoniolika
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