是非【ぜひ】
certainly, without fail, right and wrong, pros and cons
是正【ぜせい】
correction, revision, redressing, rectifying
是認【ぜにん】
approval
国是【こくぜ】
national policy
党是【とうぜ】
party platform, party principles
是か非か【ぜかひか】
right or wrong
是が非でも【ぜがひでも】
rightly or wrongly, by all possible means