にしろ〜にしろ details
Examples
whether A or B — a pair of alternatives is exhausted, and the following claim survives both
行くにしろ行かないにしろ、今日中に返事をしたほうがいい。
iku ni shiro ikanai ni shiro, kyoujuu ni henji o shita hou ga ii.
Whether you go or not, you'd better reply before the day is out. neutral
電車にしろバスにしろ、この時間はどうせ混んでるよ。
densha ni shiro basu ni shiro, kono jikan wa douse konderu yo.
Train or bus, it'll be packed at this hour either way. casual
導入するにしろ見送るにしろ、判断の根拠を明らかにしていただきたく存じます。
dounyuu suru ni shiro miokuru ni shiro, handan no konkyo o akiraka ni shite itadakitaku zonjimasu.
Whether we adopt it or shelve it, we would ask that the grounds for the decision be made clear. formal
Formation
AにしろBにしろattaches to noun phrase (schematic)
Notes
(行く／行かない) or two members of one set (電車／バス). Nouns
join bare; verbs and i-adjectives join in the plain form.
Related patterns
Similar
にしても carries this same doubled frame and is the unmarked default anywhere; にしろ〜にしろ rides する's imperative しろ and lands blunter — the pick when the speaker is closing the alternatives off rather than weighing them, which is why it heads instructions and refusals more readily than にしても does.
Lookalikes
A lone にしろ is にせよ's colloquial twin and merely GRANTS one case; doubled, にしろ〜にしろ stops conceding and ENUMERATES the alternatives it claims to exhaust — so the second にしろ is what fixes the reading, and meeting the first one mid-sentence settles nothing yet.