JMdict: 1632610

べし 【べし】

  1. [aux] must; should; ought to
  2. [aux] will (surely); be bound to; must
  3. [aux] will (do); shall
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Words often seen with this one: (experimental feature)

 (15), 眠り (12),  (12),  (12), という (12), ぐる (10), その (10)