不(ふ)時(じ) fujiに niそなえ sonaeなくてはいけない nakutehaikenai。 You must be prepared for emergencies. Literal Emergencies [for-に] prepare-not must. そなえなくてはいけない = 'must prepare.' The negative conditional + いけない obligation form. 不時 = 'emergency/unexpected event.' safety and dangeradvice and suggestions~なければならない (must)
不(ふ)時(じ) fujiに niそなえ sonaeなくてはいけない nakutehaikenai。 You must be prepared for emergencies. Literal Emergencies [for-に] prepare-not must. そなえなくてはいけない = 'must prepare.' The negative conditional + いけない obligation form. 不時 = 'emergency/unexpected event.' safety and dangeradvice and suggestions~なければならない (must)