As a language teacher I'm really interested in what learners think of i+1. This term was invented by the linguist Steven Krashen. Other research says we can't guess the +1 unless we know at least 95% of the language surrounding the unknown +1. So many professional language teachers are often obsessed with providing students i+1 to students just a tiny bit beyond what they know already. On the other hand many polyglot language learners said they interpret i+1 as the immersing in interesting content even if they only partially understand, perhaps lower than 50%, and the +1 is what comes up again and again so they check what it is and study it, piling up +1s until they are fluent. What do you think? What does i+1 mean to you?