essential basic or indispensable; necessary基本: basic; fundamental的: 4次方是 The fourth power of 2 i ...必須: must; have to; be obliged to ...必須的: compulsory; compusory; essential; indispensable to; integrant; must; necessary; obligatory; requisite必須的；應(yīng)有的: integral---essential or necessary for completeness; constituent下載手機詞典可隨時隨地查詞查翻譯
