Lesson 3 of 8
Adjective Lab — eight boxes and two liars
about 9 minutes
After this lesson you can
- Produce present, past, negative and negative past for both い-adjectives and な-adjectives.
- Inflect いい correctly instead of by its written shape.
- Recognise きれい, ゆうめい and きらい as な-adjectives despite their final い.
Words this lesson teaches
- からい
- spicy (い-adjective)
- あまい
- sweet (い-adjective)
- あつい
- hot, to the touch (い-adjective)
- いい
- good (い-adjective, irregular)
- しずか
- quiet (な-adjective)
- かんたん
- simple, easy (な-adjective)
- きれい
- clean, pretty (な-adjective, ends in い)
- ゆうめい
- well known (な-adjective, ends in い)
- あじ
- taste, flavour
What it explains
Eight boxes: four for each kind
An い-adjective changes its own ending. からいです, からくないです, からかったです, からくなかったです — the い comes off and く carries the rest. A な-adjective does not change at all; the copula behind it does, exactly as it does after a noun. しずかです, しずかじゃありません, しずかでした, しずかじゃありませんでした. This is the whole system. Which kind a word is decides which of the two columns you are in, and there is no third pattern to learn.
いい is irregular from the second box on
いいです is fine. Everything after it comes from an older form, よい, and so the rest of the row reads よくないです, よかったです, よくなかったです. There is no いかったです and no いくないです. This matters more than most irregulars because いい is the adjective a beginner reaches for most often — every time you liked something.
Ending in い does not make it an い-adjective
きれい, ゆうめい and きらい all end in い and are all な-adjectives. きれいじゃありません, not きれくないです. Nothing in the spelling gives this away — in kanji the い is not even part of the word — so these are memorised individually rather than worked out. There are only a handful of them, and you have now met three.