esstential基本: basic; fundamental的: 4次方是 The fourth power of 2 i ...必要: requisite; necessary; certai ...必要的,基本的,要點(diǎn): essential必要的,基本的,不可少的: essential to/for下載手機(jī)詞典可隨時(shí)隨地查詞查翻譯