Carpallo, Grammar sketch in the New Lakota Dictionary that you've got is the best description of Lakota Grammar. Of course the L1-L2 textbooks are for kids, they are not fully optimal for adults. CULP materials are actually the 20 first lessons of Lakota with a dictionary of 1000 most usable and frequent Lakota verbs. In fact, NLD-Online, that has almost 20,000 entries, is much more advanced tool. Besides, it is online, it recognizes all the conjugation verb forms, the words in it are clickable etc. The texts in the Forum are powered by NLDI - New Lakota Dictionary-Instant (or Inline) - if you doubleclick or mouse-select any word (English or Lakota, including conjugations), you'll get the dictionary entry for it.
The
Interactive Textbook amounts to, perhaps, first volume of the CULPt textbooks. The other topics of the Forum cover other vocabulary and grammar issues, sometimes very advanced ones. Of course this is unordered heap of topics and the carefully written textbook for adults with grammar - morphology, syntax, together with excercises, mp3s and all that would be great - it is in the LLC's agenda, but not for the nearest future - the L4, L5, etc. textbooks for school are under way, this is more important for language revitalization.
I guess that for us, adults the best way to become fluent in Lakota is a combination of permanent practising of Lakota speaking with fluent speakers, ideally, immersion - when you only hear Lakota speech and talk Lakota --to the best of your ability - and learning grammar in a "grownup way" - from professional linguists or their textbooks.
If we cannot learn in a perfect way, we should learn as much perfect as possible - for example, reading the texts written by native fluent speakers, or reading grammar sketches, and asking questions in a forum

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