I'm trying to attempt to learn the language as my third language.
http://www.uesp.net/wiki/Lore:Dragon_Language
There's a page with probably all the dragon language words.
I counted 156 words in the first column, lets multiply that by 3 and you get 468 words we know, rough estimate. I heard for a language you need to learn the most common 1000 words before you become fluent. So we need to fill in about 500 words, also most of the words were nouns, we need more verbs, adjectives, etc etc, and grammar rules