How second-language acquisition (SLA) research shaped our approach
Most language learning apps focus on memorization: vocabulary lists, grammar drills, and translation exercises. While these methods feel productive, research shows they're not how humans naturally acquire language.
Think about it: no child ever learned their first language through flashcards. They learned by being immersed in meaningful communication.
In the 1970s and 80s, linguist Dr. Stephen Krashen developed the Input Hypothesis, which revolutionized our understanding of language acquisition.
Author of more than 525 articles and books on bilingual education, neurolinguistics, second language acquisition, and literacy. One of the most highly cited researchers in the field.
Krashen's core insight: we acquire language when we understand messages. Not by studying rules, not by memorizing words, but by comprehending meaningful input that's just slightly above our current level.
The "i + 1" Formula: Optimal learning happens when input is comprehensible (i) plus just a little bit new (+1). Too easy and you don't learn. Too hard and you can't understand.
Subsequent research has refined Krashen's theory. Studies now show that learners need to understand 95-98% of input for optimal language acquisition.
This finding has been replicated across multiple studies:
The Problem: Native content like Netflix, video games, and Reddit typically contains far more than 5% unknown words for intermediate learners. This makes natural immersion ineffective for most people.
You've probably heard "just watch Netflix in English" or "immerse yourself." While well-intentioned, this advice ignores a crucial problem:
Native content is too hard for most learners.
When you understand less than 95% of what you hear, your brain can't efficiently acquire the new vocabulary. You're overwhelmed, frustrated, and not actually learning.
This is why many learners spend years watching English content without significant improvement. The input isn't comprehensible enough.
Termy makes native content comprehensible by giving you instant explanations of difficult words and phrases. Instead of being overwhelmed by unknown vocabulary, you get immediate context that keeps you above the 95% threshold.
The result: You can watch the content you actually want to watch while maintaining the comprehension level needed for effective acquisition.
This approach combines the best of both worlds:
SLA research is a nuanced field with ongoing debates. Many researchers emphasize that interaction, feedback, and output also play important roles in language learning. Termy doesn't claim that input alone is sufficient for mastery.
What we do claim: improving comprehension in the moment makes real content usable for learning. Termy is a lightweight scaffold that helps you stay above the comprehension threshold while engaging with content you enjoy.
Primary sources and academic references
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