GRAMMAR TOOLS
Japanese Adjective Forms
Japanese adjectives change depending on whether the sentence is affirmative or negative, and present or past.
There are two main adjective types:
い-adjectives and な-adjectives.
Nouns also follow a very similar sentence-ending pattern to な-adjectives.
01
Adjectives & Nouns
First, learn the two adjective types — and how nouns fit into the system.
い-adjectives
Many い-adjectives end in い.
な-adjectives
Use な when the adjective comes directly before a noun.
Nouns behave like な-adjectives at the end of a sentence.
Their present, negative, and past endings follow almost the same pattern.
な appears before a noun — not before です.
Before a noun:
きれいな部屋
At the end of a sentence:
部屋はきれいです。
✕ 部屋はきれいなです。
Nouns use の before another noun.
Not every adjective ending in い is an い-adjective. きれい is a な-adjective.
02
How They Change
Let’s compare the four basic polite forms.
おいしい
delicious
いい
good
In negative and past forms, いい changes to よ….
きれい
beautiful / clean
きれい + です
きれい + じゃないです
きれい + でした
きれい + じゃなかったです
じゃ is commonly used in conversation. You may also see ではないです and ではありません.
ではありません is especially common in more formal or polite situations.
がくせい
student
03
Plain Forms
Plain forms are used in casual conversation and before many grammar patterns.
おいしい
✓ おいしい
✕ おいしいだ
きれい
がくせい
Sentence-final だ is often omitted.
Especially in simple reactions, Japanese speakers often finish with the adjective or noun itself.
But sometimes you need だ.
Before some grammar patterns, な-adjectives and nouns use だ.
04
Adjective & Noun Practice
Choose a word and a form. Say the answer, then check it.
MAKE THIS FORM
おいしい
delicious
ANSWER