The word "lii" is an unusual spelling, but it is often used to represent the sound of a sustained high-pitched note. Its phonetic transcription is /li/. The two letters "i" represent the long "ee" sound, making it a monophthong, while the final letter is meant to elongate the sound. It is frequently used in music notation and often found in vocal music, where it is important to indicate the length and pitch of the note to be sung.