铅笔勾勒出的黑色画面粉笔勾画出的白色画面
[qiān bĭ gōu lè chū de hēi sè huà miàn fĕn bĭ gōu huà chū de bái sè huà miàn]
Translates to 'Black Pictures Drawn by Pencil, White Sketches Delineated by Chalk'. Using drawing materials as metaphors for life experiences; contrasting black with white can indicate different aspects or feelings in different contexts. Maybe suggesting the contrast between past darkness and purity in one's present state.