Czech language:

During the revival, in 1809 linguist and historian Josef Dobrovský released a German-language grammar of Old Czech entitled Ausführliches Lehrgebäude der böhmischen Sprache (Comprehensive Doctrine of the Bohemian Language). Dobrovský had intended his book to be descriptive, and did not think Czech had a realistic chance of returning as a major language. However, Josef Jungmann and other revivalists used Dobrovský's book to advocate for a Czech linguistic revival. Changes during this time included spelling reform (notably, í in place of the former j and j in place of g), the use of t (rather than ti) to end infinitive verbs and the non-capitalization of nouns (which had been a late borrowing from German). These changes differentiated Czech from Slovak. Modern scholars disagree about whether the conservative revivalists were motivated by nationalism or considered contemporary spoken Czech unsuitable for formal, widespread use.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". What kind of revival was called for by Josef Dobrovsky?
unanswerable