Showdown in the Shadow Lands
To learn a new language, the character must be first exposed to the language, then succeed a series of Intelligence (Investigation) checks over the coarse of weeks. Each step takes one week. A failed check can be retried in one week if failed by 5 or less or next level up if more.
1st DC 15 to recognize the language
2nd DC 15 to glean some gist of the document or spoken conversation
3rd DC 20 to read the document or understand spoken conversation
4th DC 20 to translate documents or speak the language