Three readings depending on context: (1) duration '
六日' = six days; (2) date '
五月六日' = May 6th; (3) shorthand for
周六日 /
礼拜六日 = the weekend (Saturday + Sunday), e.g.
六日不上班 'closed weekends.' Tone in pinyin is liù-rì in all three; meaning is purely contextual.
