待你长发及腰为你剪掉可好
[dài nĭ zhăng fā jí yāo wéi nĭ jiăn diào kĕ hăo]
Expresses anticipation towards someone’s physical changes and willingness to change something (even as trivial as cutting off one's hair) together at a certain stage of their relationship, implying a commitment and dedication to each other.