滾降率roll: vt. 1.滾,轉(zhuǎn),推滾(桶、車輪等),使(煙、塵土)滾 ...off: adv. 1.〔運動〕向那邊,隔開。 be off 走, ...rate: vt.,vi. 〔方言〕=ret. roll off: 滑離; 推出; 輾軋; 轉(zhuǎn)降roll on-off: 滾式裝卸下載手機詞典可隨時隨地查詞查翻譯