待你长发及腰少年已为人夫
[dài nĭ zhăng fā jí yāo shăo nián yĭ wéi rén fū]
This phrase expresses a bittersweet feeling of waiting and losing someone. It roughly means: 'When you grow your hair long enough, the young man you were waiting for is already married to someone else.' It conveys regret and nostalgia.