Danci Danyu
Learn words by their roots, master them through play
iOS · An English vocabulary tool for Chinese native speakersWhat this app does
Why do you memorize a word and forget it again? Most of the time it isn't a memory problem — you never really understood the word.
Danci Danyu uses 604 roots and affixes to take each English word apart and reveal how it is built, 12 practice modes to fit memory into spare moments, and the SM-2 spaced-repetition algorithm to schedule exactly which words to review today. Five minutes a day turns English vocabulary into something you can actually use.
The data behind it
Core features
Learn by roots
English and Chinese definitions, typical examples, and related words for 604 roots and affixes. Learn one root, remember a whole family of words.
12 ways to practice
Classic study: flashcards, multiple choice, spelling, fill-in-the-blank, smart review
Game challenges: whack-a-mole, stack tower, speed runner, bubble shooter, fruit slice, word black hole, triple-match
Each one targets a different stage of memory — recognition, retrieval, spelling, reaction, consolidation.
The 7R method + SM-2 spaced repetition
Repeat / Recall / Relevance / Reason / Recode / Run / Rest — seven core principles from cognitive science. The SM-2 algorithm automatically computes the next review time for every word.
AI Learning Assistant (optional)
With DeepSeek connected, the app gains a few extra abilities:
- Smart word breakdown: word formation, etymology, and a mnemonic in one line
- Learning diagnosis report: finds the words you forget most and your weak roots
- Custom word-set generation: say "give me 20 airport words" in chat and it's added automatically
- AI study chat: ask "how do I remember this word" or "which words do I keep forgetting" any time
The AI part requires a CN¥9.9 / month subscription in mainland China, or use your own DeepSeek API key for free. In Singapore, Malaysia, Hong Kong, Macau, and Taiwan the price differs and follows the App Store for your region. Everything else is free forever, with no ads and no paywalled unlocks.
Privacy
All learning records, favorites, and self-built word sets stay on your device — no account or device information is uploaded. AI calls send only the English word you are looking up or a short learning summary, with no identifying information. You can turn off all networking in Settings.