Blocked vs Interleaved Practice for Japanese Grammar

KOTOBA BREW

第034号 · Issue 034

Mix What You Keep Mixing Up

{{first_name | みんな}}さん、こんにちは ☕

Here is a test that takes about nine seconds.

Think of a grammar point you could happily explain to a beginner right now. Got one? Good. 👀

Now think about the last time you had to choose that point, inside a sentence somebody else wrote, with nothing in the question telling you which one was being asked.

If those two things feel different, drilling that point again will not close the gap. The gap was never about that point on its own.

Know someone who can explain every rule and still picks the wrong one? Send them this. Share this issue →

Two near-identical forms overlapping, printed out of register

Knowing what it means and knowing when to pick it are two different skills

You have answered your flashcard for 〜おかげで correctly maybe forty times. Every single one of those forty times, 〜おかげで was the only thing being asked.

That is not a test of whether you can choose it. It is a test of whether you can recall a label. 💡

Your textbook does the same thing, one chapter at a time. So does most SRS grammar, where a hint field quietly narrows the answer before you have finished reading the sentence. And your prep book groups similar points together, which genuinely helps you study the contrast, then drills them one at a time anyway.

So you end up fluent in the explanation and shaky in the moment. That is not a memory problem. It is a discrimination problem, and discrimination only trains against rivals. 😅

The question is not "am I good at this". It is "have I met this at all".

Here is the whole rule.

→ If you cannot yet state what it means without checking, keep it blocked. Drill it alone. Mixing now just makes you slower and wronger, and buys nothing back.

→ If you can state the rule cold but still pick wrong in real sentences, stop drilling it alone. Shuffle it with its two nearest rivals and answer them mixed.

→ If you can state it and you pick it right in context, leave it alone. It does not need a slot. 💪

The trap is reading rule one as "block it until you are good at it". That would have you blocking forever. The line is whether the pattern exists in your head at all, not whether you have mastered it.

一
言

☝️ Chotto ちょっと

There is a second half almost nobody mentions, and it is the part that actually works. Mixing at random does nothing on its own. What pays is comparing the rules side by side, in an orderly way, and then retrieving them in an order you cannot predict. Study them neatly. Test them shuffled. 🎯

Take に and で, which you were probably taught as "に with ある and いる, で with action verbs". That rule breaks almost immediately. 住（す）む looks like an action and takes に: 東京（とうきょう）に住む, but 東京で働（はたら）く. And ある takes both, depending on what is going on: 会議室（かいぎしつ）に机（つくえ）がある, but 会議室で会議（かいぎ）がある.

The version that survives contact: に marks where something exists or ends up. で marks the setting an event happens in. 関東（かんとう）で地震（じしん）があった, because an earthquake happens, it does not sit there. 👀

You will not internalise that from a に drill. You get it from に and で landing in front of you in an order you cannot guess.

Two stacks of blank cards riffle-shuffling into one another

危険	⚠️ Abunai 危（あぶ）ない This will feel worse before it feels better, and you need to know that going in or you will quit in week one and conclude it does not work.

In the study this comes from, the mixed group was about ten points less accurate during practice than the blocked group. On the test straight afterwards there was no difference at all. The mixed group only pulled ahead a week later. So: lower scores now, better recall later. If you judge it on Tuesday's accuracy you will judge it wrong. 📚

This Week's Japanese

Word of the Week

紛（まぎ）らわしいNeutral, everyday

Means: confusingly similar. Close enough to something else that you mix them up. Which is this entire issue in one adjective. 📌

Use it: ordinary spoken Japanese, and it turns up on warning labels too. この二（ふた）つの漢字（かんじ）は形（かたち）が紛らわしい。

Kanji of the Week · 漢字

紛

Meaning: to become mixed in, to blur together until you cannot tell things apart.

Reading to learn first: まぎ. On'yomi is フン, as in 紛失（ふんしつ）, losing something in the shuffle.

Common words: 紛失 loss · 紛争（ふんそう）dispute · 紛（まぎ）れる to get mixed in

Memory hint: the character is about things intermingling until they lose their edges. That is not a metaphor for your grammar problem. It is a description of it. ⚡

One caution: 紛らわしい is not simply "the adjective form of 紛れる". Its closer partner is 紛（まぎ）らわす, to make something indistinct.

A blank card with a rectangular hole cut where a word would be

Renshuu Time 練習（れんしゅう） 📝

Ten minutes. Two pairs you have already studied and still get wrong. This does not work on new material.

→ Starter: Pick your two pairs. Write down, from memory, what separates each one. Do this before you look anything up.

→ Standard: Find eight real sentences, four using each pattern, from Japanese you did not write. 少納言（しょうなごん） is free, needs no account, and searches about 100 million words of real published Japanese. Blank out only the pattern. Leave the context. Shuffle the eight so you cannot predict which is next, then answer cold.

→ Challenge: Score the direction of your errors, not the total. Writing せいで where おかげで belonged, three times out of four, is one specific confusion with a fixable shape. "I am bad at N3 grammar" is not.

You will know you did it when: you can name which way your mistakes go.

✨ Yatta やった

You just built a test your textbook cannot give you, because a textbook chapter always tells you which pattern is being asked. You took the cue away. That is the whole trick. 🙌

The tiny win

You now have a rule for deciding where your study time goes: block what is new, mix what keeps losing, leave alone what already works. Most people give all three the same treatment. 💪

One reply back

Hit reply with the pair you keep mixing up. Just the two patterns, nothing else.

We read every one, and if the same pair shows up enough times it becomes an issue. 👀

Stay connected 🙌

We are around during the week if you want to talk shop, share a win, or just lurk. Both are completely fine.