白衫故人梦里归人
[bái shān gù rén mèng lĭ guī rén]
The phrase evokes the imagery of an old friend or acquaintance (possibly romantic) who is remembered while wearing a white shirt. The person also visits in dreams as the 'one returning,' suggesting themes of longing and nostalgia for a past relationship. It captures a dreamy, poetic sentiment of remembering those left behind, with the added nuance that the memories are often more idealized when they appear in one’s dreams.