unavoidably determined by prior circumstances; "the necessary consequences of one's actions"やむを得ず、事前の状況で決定される必然的
例:The necessary consequences of one's actions. 人の行動の必然的な結果。
absolutely essential必要不可欠な須要
anything indispensable; "food and shelter are necessities of life"; "the essentials of the good life"; "allow farmers to buy their requirements under favorable conditions"; "a place where the requisites of water fuel and fodder can be obtained"不可欠な何でも必須