modality N1 rare literarywritten
いかに〜(こと)か — how very ~!
いかに〜(こと)か ・ いかにことか
Builds on いかに
A full written guide for いかに〜(こと)か is on the way.
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See いかに〜(こと)か in real sentences
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Study it in JengoSources Editorial confidence: medium.