In 4e, Language is pretty much all or nothing. You can either speak a language very well, or you can't speak it at all. The only wiggle room in the rules as written in the Nationality (Languages) subsection of the Character Creation chapter. It states (paraphrasing here) that everyone speaks a little English, and that Warsaw Pact personnel all speak a little Russian.
A PC can learn another language in the game by using skill points to take the Linguist Specialty. However, according to that rule, adding that specialty could conceivably take a PC from not being able to speak a lick of another language to being mistaken for a native speaker of it!
INGUIST: You know another language of your choice, well enough to be taken as native on a successful PERSUASION roll. (p. 51 of the Player's Manual)
As anyone who's learned a second language can attest, it takes time to learn and build proficiency and fluency- sometimes years! I lived in South America for 6 years as a teenager and I still wouldn't consider myself fluent in Spanish.
In v2.2, at least, you could be a little proficient, or moderately so, or fluent, by allocating skill points to a second language. It was tricky (and pretty subjective) to determine how well a PC could speak another language in that ruleset because it wasn't really clearly explained what the numbers meant, but at least there were degrees of proficiency.
How have other 4e ref's dealt with acquiring additional languages?
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