It can be dangerous to let too much soot accumulate inside a chimney.烟囱里堆积过多的煤灰是很危险的。The air was black with diesel fumes and coal dust.空气中充斥着黑乎乎的柴油烟和煤灰。Matthew scrubbed the coal dust from his face.马修擦掉了脸上的煤灰。Factory chimneys showered soot on the district.工厂的烟囱把大量煤灰倾吐在这一地区。