The data comes from a test I built that measures receptive vocabulary — the number of words a person recognizes (but may not necessarily use). It places everyone — from a student who has just started learning English to an educated native speaker — on the same scale. The units are word families (so limit, limited, and limitless count as a single unit). Users self-reported their CEFR levels.
It’s striking to see how much one has to learn to progress from level to level and potentially reach the native range.
by RevolutionaryLove134