铅笔画不出的界限橡皮擦不掉的间隔
[qiān bĭ huà bù chū de jiè xiàn xiàng pí cā bù diào de jiān gé]
'The boundaries that can't be drawn with a pencil, the intervals that can't be erased with an eraser.' This expresses a sense of insurmountable differences and separation between entities. It symbolizes issues beyond superficial marks—representing deeper and perhaps more complicated divisions such as ideological, cultural, emotional that aren't easily resolved or forgotten like written marks on paper.