as hard as the nether millstoneæzhɑrdæzðəˈneðəˈmilstəun 基本例句 adj.铁石心肠的 用作形容词The dictator was a man of great hardness of heart.那个独裁者是一个铁石心肠的人。 One would need to have a heart as hard as stone not to be moved by his pitiable plight.他的境况十分可怜,只有铁石心肠的人才会不为所动。