HSK 4 · Mastery learning

Master HSK 4 — and the questions that make you conversational.

A mastery-based system modeled on Math Academy: adaptive diagnostic surfaces your knowledge frontier, a graph of ~130 HSK-4 topics structures what to learn next, nothing new unlocks until you can prove what you know, and spaced repetition keeps everything you've mastered from fading.

Try a real HSK 4 exercise

Cloze · 填空 把-construction · 第28课
Choose the correct word to complete the sentence

他把护照___在出租车上了。

Tā bǎ hùzhào ___ zài chūzūchē shàng le.

Complete exercises like this to earn XP and unlock the next topic
The curriculum

130 topics. Every one locked until you've mastered what it's built on.

The full HSK 1→6 knowledge graph — same idea as Math Academy's famous curriculum map, but for Mandarin. Hover any node to see the topic. Click to highlight its prerequisite chain. HSK 4 is where you start.

HSK 1 HSK 2 HSK 3 HSK 4 — available now HSK 5 — coming after HSK 6 — on the roadmap
Mastered Frontier Locked Click any node to highlight its prerequisite chain
Loading knowledge graph…

Preview dataset (~95 of 130 topics). Full graph builds from the HSK vocabulary + grammar corpus in Phase 2.


How it works

Mastery learning — the Math Academy method, for HSK 4.

Not a course you push through regardless of what you've retained. A system that only moves you forward when you've actually learned what came before.

Step 1 · Diagnose

Free adaptive diagnostic

20–40 questions, binary-search style, maps your exact knowledge frontier across all ~130 HSK-4 topics. Free. No account needed at first.

Step 2 · Learn on your frontier

Study at the edge of what you know

The system finds topics where all your prerequisites are mastered and serves you those lessons first — grammar, vocab clusters, and conversation drills together.

Step 3 · Prove mastery

Nothing unlocks without evidence

Each topic requires a rep score ≥ 2.0 before its dependents open. Timed quizzes every 150 XP verify retention across everything you've learned.

Hard rule: a topic stays locked until every prerequisite is mastered — no skipping, no workarounds.
Step 4 · Never forget

Spaced repetition keeps it alive

FIRe-lite decay scheduling surfaces reviews exactly when memory is about to slip. Mastered topics propagate credit to related topics; failures propagate warnings back up the graph.


What's included

Every modality HSK 4 actually tests.

Vocabulary in context

All 600 new HSK 4 words drilled in authentic sentences — MCQ, cloze, and sentence ordering. Every word appears in at least two exercises per topic.

Grammar mastery

~60 grammar points (把-construction, resultative complements, 越…越…, and more) taught with worked examples and tested with graded exercises at three difficulty levels.

Conversation drills

2–3 spoken question patterns per topic — the memorize-questions→conversation method. Auto-graded best-response MCQ counts toward mastery; self-rated speak-aloud builds fluency.

Knowledge graph

~130 topics in a dependency DAG — vocab clusters, grammar points, and skill topics. Mastering a topic propagates partial credit to related ones; failing flags them for review.

Timed quizzes

10-question, 10-minute quizzes fire every 150 XP. Score ≥70% earns a rep bonus; below 70% triggers a targeted remediation task before any new topics unlock.

Spaced repetition

FIRe-lite: memory decays as a half-life function of your interval. Reviews surface when memory drops below 50%. Intervals stretch from 1 day to 120 days as you demonstrate retention.


掌握
Early access · founding member price
$199
lifetime access · one payment, yours forever
or $19/month · cancel anytime
  • Adaptive diagnostic — maps your exact HSK 4 frontier
  • ~130 topics: 60 grammar + 55 vocab clusters + skill topics
  • 600 new words in context — every HSK 4 word drilled
  • Conversation drills: question patterns + best-response MCQ
  • Timed quizzes with targeted remediation
  • FIRe-lite spaced repetition — nothing fades quietly
  • Daily XP goal (default 20 XP) + streak tracking

Stripe integration ships in Phase 5 — get notified below and lock the founding price.

Less than one tutoring hour per month — with a system that never forgets what you need to review.

A single tutor session costs more, doesn't track what you actually retain, and ends when the hour does. HSK Mastery works every day at the exact edge of what you know.


Free diagnostic

Get your HSK 4 knowledge map — free.

The adaptive diagnostic is free and always will be. Enter your email and we'll send you access the moment it launches, plus a personalised report of your frontier and first lessons.

No spam. One email when the diagnostic is live. Unsubscribe any time.

You're on the list — we'll email you when the diagnostic launches.

Stop grinding vocab lists. Start proving mastery.

The diagnostic is free. Take it, see your frontier, and start learning at exactly the right level.

Get the free diagnostic