nigrescent
adj. 发黑的;带黑的;易于变黑的
例句
Labial color is darker, nigrescent reason?
嘴唇颜色比较暗,发黑的原因?
In front of the door, there was no signboard of America Hotel hung, it was the same as other house, there was a heap of nigrescent firewood, and a washing line for drying clothes.
门口并没有挂什么“美国饭店”的招牌,和别人家一样,堆着一堆发黑的柴禾,拉着一根晾衣裳的绳子。