CoC Rule Summaries and House Rules
The 6th Edition rules for Other Language make no sense: “A character needs INTx5 or better points in a second language to pass for a native speaker.” In other words, the smarter you are the more points you must devote to the skill. So, the smarter you are, the harder it is to learn a second language?!
The house rule is that 30% in an Other Language skill is sufficient to be able to have normal conversation without any troubles. Higher percentage is only required for more difficult or advanced discussion/reading.
Here is the reasoning:
The Own Language skill base percentage is EDUx5. Education is 3d6+3. This means that the lowest score a character can have for EDU is 6; therefore, the lowest percentage a character can have for Own Language is 30. And it is assumed that even the least educated person can hold a normal conversation with another native speaker, and (in today’s society) can read basic text.
Assume that normal conversation is an easy task. This means that the skill percentage for this task is doubled, meaning that even the least educated person will have 60% to hold a normal conversation. Since it is assumed that a native speaker can have a normal conversation with any other native speaker without needing to roll a skill check, by the same token a 30% in Other Language should allow a character to have a normal conversation and read basic text in the other language.
However, if the conversation or text includes more advanced words, phrasing, or topics, it becomes a normal task: meaning a character that does not have 60% in the Other Language skill must roll a skill check to successfully understand the entire content of the conversation or text.