Present, Future 足りない is [x] 足りなくない is not [x] Past 足りなかった was [x] 足りなくなかった was not [x] Te-form, Continuative 足りなくて is [x] and... 足りなくなくて is not [x] and... Provisional 足りなければ if it is [x] 足りなくなければ if it is not [x] Conditional 足りなかったら when/if it is [x] 足りなくなかったら when/if it is not [x] Adverbial 足りなく [x]-ly Noun form 足りなさ [x]-ness