待你长发及腰我就咔嚓一刀
[dài nĭ zhăng fā jí yāo wŏ jiù kă cā yī dāo]
'When your hair grows to reach your waist, I'll cut it off with a snip' could suggest a playful, possibly affectionate intention, perhaps implying a relationship's progression where actions speak louder than words.