词汇：indispensable

adj. 不可缺少的；绝对必要的；责无旁贷的

相关场景

This willingness to work on the ground was indispensable, for most cowboys would rather eat poison than be forced to dismount. They all fancied themselves ropers, and swelled like toads if asked to do work they considered beneath their dignity.

>> Lonesome Dove 孤鸽镇

-lt's indispensable in a bureaucracy.

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