待你长发及腰送你一把剪刀
[dài nĭ zhăng fā jí yāo sòng nĭ yī bă jiăn dāo]
A humorous and somewhat paradoxical phrase expressing that 'when you grow your hair long, I'll give you scissors'. It implies a contradictory situation where the speaker wants someone to do something but offers an action that negates it.