JMdict: 2785230

せねば

1. [exp] ought to do; have to do; must do; feel obliged to

Words often seen with this one: (experimental feature)

ならん (106), なんとか (28), この (25), 私 (22), なる (21), こと (17), なんで (14), しっかり (14), その (13), 報告 (13), こんな (10)