The ill-usage of children is the blackest mark against the Industrial Revolution.虐待儿童是工业革命的最大污点。This was one of the blackest crimes ever committed.这是迄今犯下的最令人发指的罪行之一。It was, he said later, one of the blackest days of his political career.后来他说，这是他政治生涯中最黑暗的日子之一。