Present, Future 説き難い is [x] 説き難くない is not [x] Past 説き難かった was [x] 説き難くなかった was not [x] Te-form, Continuative 説き難くて is [x] and... 説き難くなくて is not [x] and... Provisional 説き難ければ if it is [x] 説き難くなければ if it is not [x] Conditional 説き難かったら when/if it is [x] 説き難くなかったら when/if it is not [x] Adverbial 説き難く [x]-ly Noun form 説き難さ [x]-ness