短語詞組短語back bone lining up machine 書脊粘紗布機bone up detail 抓緊溫習bone up World 努力研讀bone up on 努力研讀;專心致志于;專門鉆研;鉆研to bone up on 鉆研bone up for 突擊鉆研bone up to 學習bone up on a subject 專攻一門學問Bone up on a problem 突擊鉆研一個問題 返回 bone up