The core course closes its grammar at twenty frames — after Lesson 9, growth is pure vocabulary. Boosters are how that growth ships: small, themed boosters you add only when your trip actually needs one. Each booster is roughly 15–30 nouns plus a few recognize-only phrases, dropped straight into frames you already own — no new grammar, ever. Same format as the lessons: audio on every item, tap-to-reveal, and a small Anki deck. (Modules that extend the system itself — reading katakana, number speed, real prices, dates, clock minutes — live in Skills.)
And the words are only half of each booster. Every booster carries the scene’s etiquette — the behavior notes where the correct move is invisible to outsiders — and usually one Japan-specific unlock: a system most visitors never learn exists at all. Sending your suitcase ahead by takkyuubin, the ticket machine running half the country’s ramen shops, the ryokan curfew, the tax-free counter’s sealed bag, the bear bell at the trailhead. A dozen new nouns are nice; knowing the machine exists is what changes the trip.
Two honest cautions. Japan changes: prices, tax rules, transit passes, hours, and procedures in these pages were correct when written and will drift — the Japanese will keep working long after a fee or rule has moved on, so when a real-world detail matters to your plans, verify it against a current source. And this course was built with substantial help from AI: it has been reviewed with care, but a factual error may have crept in somewhere despite that. Trust the frames; double-check the facts.
Shipped boosters are listed below — take them in any order, whenever the trip calls.
Need a theme we haven’t packed?#
The noun layer is open by design, and the AI translator knows it: ask it for the sentences your trip needs — golf, fishing, a wedding, a hospital visit — and it will build them from frames you already own, marking any new nouns as it goes. Harvest the rest in the field with Lesson 2’s Kore wa nihongo de nan desu ka. A booster is just this, curated — you can improvise your own any time.
~7 nouns, no new grammar. The pre-flight checklists, the scripted first hour, the one word immigration wants, the hotel bag-drop — and a friendly tutorial for your first Japanese toilet.
~7 nouns, no new grammar. The city’s hardware layer — the IC card, the gates, the numbered exits, the bus button and the country bus’s numbered slip — for the transit you ride every single day.
~10 nouns, no new grammar. The ¥900 lunch in all its formats — the teishoku tray and its free rice refills, the daily special, the famiresu, the fast-food counter — and breakfast for the price of a coffee.
~18 nouns, no new grammar. Walk into a hot spring or neighborhood bathhouse, ask the tattoo question, and get in the water without breaking a single rule.
~10 nouns, no new grammar. The tatami room, the futon that appears while you eat, the kaiseki rhythm, and the curfew question — the whole night around the bath.
~12 nouns, no new grammar. The department-store food hall: sampling etiquette, buying by the hundred grams, the evening half-price bloom, and gift-wrapping with noshi.
~15 nouns, no new grammar. Order the first round, decode the mystery appetizer, split the bill, and — above all — make the last train.
~9 nouns, no new grammar. The time-block system again, the drink bar, the T-minus-ten phone call — and permission to sing badly, loudly, or alone.
~15 nouns, no new grammar. Book a shinkansen seat at the Green Window, ask the pass question before boarding, and eat a station bento at 285 km/h.
~14 nouns, no new grammar. Headache, blister, cold, upset stomach — the drugstore run every trip eventually makes, from the right shelf to Odaiji ni.
~9 nouns, no new grammar. Send the suitcase ahead to the next hotel or the airport, fill in the slip, claim it with your name — and chase it with the tracking number if it hides.
~15 nouns, no new grammar. Enter the gate correctly, wash, wish, draw a fortune, collect a stamp — and ask before every photo.
~12 nouns, no new grammar. The conveyor belt and the counter: plate colors, touchscreen orders, the omakase handoff, and wasabi diplomacy.
~7 nouns, no new grammar. Rain-season umbrellas, weather small talk, and the announcement that tells you Japan is stopping its trains tomorrow.
~11 nouns, no new grammar. The full declaration, the dashi problem, and the happy paths — eating to your rules in a country that cooks fish stock into everything.
~11 nouns, no new grammar. The shokken system — buy the ticket before you sit — plus broth choices, upsizing, and the glorious noodle refill.
~17 nouns, no new grammar. Claim the tourist tax exemption, survive the fitting room, pick a color and a size, and get the gift wrapped.
~10 nouns, no new grammar. The time-block system, the treat cup, and the three house rules — sleeping cats are off-limits, flash never, and Ojikan desu means it’s over.
~15 nouns, no new grammar. Find the matsuri, eat your way down the stall row, join the dance, and know when the fireworks start.
~15 nouns, no new grammar. Sumo, a ball game, a show: buy the ticket, find your seat, and know when to actually arrive.
~9 nouns, no new grammar. The locker that eats your shoes, the wristband key, the free earplugs at the desk, and the one law of the pod floor: silence.
~10 nouns, no new grammar. Buy the postcards, stamp them for anywhere on Earth, ship a box of omiyage by sea — and answer the customs question with one noun.
~16 nouns, no new grammar. Pick a mountain, find the trailhead, ask about bears and water like you mean it — and greet every hiker you pass.
~16 nouns, no new grammar. Rent the bike (electric if it’s hilly), find the cycling road, park it legally — and report a flat in one word.
~8 nouns, no new grammar. Where a tent is welcome in Japan — campgrounds, roadside stations, mountain tent sites — and the one question that turns grey zones into welcomes.
~6 nouns, no new grammar. Buy online mid-trip — pick it up at a konbini counter, a locker, your hotel, or any post office. No address required.
~9 nouns, no new grammar. Japan’s pay-by-the-hour living room — manga, PCs, free drinks, a shower — and the night pack that doubles as the country’s cheapest bed.
~13 nouns, no new grammar. Where you’ll actually stay, laundry, the supermarket sticker hour, garbage rules, and a haircut — the systems that only start mattering after week two.