un. 換油周期 change over period: 轉(zhuǎn)換周期change over: 掉期; 改變成; 轉(zhuǎn)換; 轉(zhuǎn)接change-over(change of ends): 換邊inventory change summary period: 庫存變更總計期間oil change period: 換油周期下載手機詞典可隨時隨地查詞查翻譯