唯一: only; sole; unique不可缺少: indispensable; requisite; es ...的: 4次方是 The fourth power of 2 i ...不可缺少的: indispensable; obbligato不可缺少的东西: breath of life不可缺少的条件: indispensable conditions不可缺少的原因, 不可缺少的条件: causa sine qua non必须的条件，不可缺少的东西: a must起到了不可缺少的作用: play indispensable roles不可缺少: indispensable; requisite; essential; absolutely necessary; indispensability; vital对…不可缺少: be essential to绝对需要的, 不可缺少的, 极重要的: of the essence空气，食物和水是生命不可缺少的东西: air,food and water are things essential for life我可以是你不可缺少的空气: i could be your breath of life可一而不可再: may be done once, but may not be repeated; once is forgivable, not twice.; once is enough缺少的: absent; missing; poor; short; stringent平时不可缺少而危急时反为累赘的船具: hamper不可缺的: obligato不能缺少的: sine qua non穷的, 缺少的: badly off缺少的，找不到的: missing缺少的一张牌: missing card血小板缺少的: platelets-poor必不可少的: essential; imperative; indispensable for; vital不可少的: imperative; requisite
