Thus far we have been using the suffix -gaar to make adverbs such as stingaar ("freely") or nonvulgaar ("nobly"). As I've been putting together the new lessons, my understanding of the language has changed, and I have some information that disqualifies -gaar as a semi-canon suffix, and adverbs in Dovahzul in general.
-gaar originated from the word zohungaar, the canon word for "heroically". However, this doesn't work because the word hungaar means "heroic". It might seem confusing that the prefix zo- is making the adverb here, but with some further explanation this makes perfect sense.
Zohungaar is the only canon Dovahzul adverb (that follows the "-ly" pattern). In the official game guide, it lists one adverb besides this: "Voth Ahkrin" - bravely. This literally means "with courage". My new theory on adverbs is that they don't exist as individual words, but can be formed using voth with nouns. So if you wanted to say "freely", you would say "with freedom". If you wanted to say "peacefully", you would say "with peace".
We know that zo- is equivalent to English's "-ful". Zohungaar then means something along the lines of "heroic-ful", or "with heroism". Zo- is not really a suffix for adverbs, just another way to express "with ____".
I propose that the suffix -gaar be removed and all adverbs that make use of it deleted. Then, we can correctly express adverbs using "with ____". Existing words that use zo- can also be adverbs, so something like zovahzen would mean both "truthful" and "truthfully / with truth".