刻骨铭心的咬牙切齿
[kè gú míng xīn de yăo yá qiè chĭ]
It expresses an extremely bitter and resentful mood, indicating intense anger and frustration, almost to the point of etching deep into the heart (translated directly from the literal meaning 'engraved in the bone'). It depicts someone being filled with rage and helplessness.