Subtitles that flag the words worth learning

As you watch, the captions mark how common each word is. Hit a word you don't know? The highlight tells you whether it's an everyday word, one of the most common 500, 1,000, or 2,000 in the language, or something genuinely rare. So you decide on the spot: look it up and learn it, or let it slide and follow the gist. You don't have to understand every single word.

To make this actually useful, we don't judge a word by the exact form it shows up in. We flatten every word back to its base first, so recordármelo counts as recordar. We use LLMs to do that mapping. In our early testing that's the part that makes it work: without it, loads of essential high-frequency verbs look technically rare just because they turned up in a less common conjugation, even though they're words you absolutely need.