Japanese i-adjectives and na-adjectives: two useful patterns

Japanese adjectives often become easier to recognize when you learn them with a noun. Start with two short phrases: warm tea and a quiet room.

温かい: an i-adjective

温かい means “warm.” Before a noun, use 温かい directly. You do not add な between this adjective and the noun.

In a polite sentence, you can say このお茶は温かいです。— “This tea is warm.” Notice that the い remains before です.

静か: a na-adjective

静か means “quiet.” Before a noun, add な. This connection is the reason learners often call this group “na-adjectives.”

At the end of a polite sentence, use 静かです: この部屋は静かです。— “This room is quiet.” The な connects the adjective to a following noun; it does not go before です.

An i sound does not always mean an i-adjective

きれい (kirei, “beautiful” or “clean”) ends in an i sound, but it belongs to the na-adjective group. A clean room is きれいな部屋. Learn the group with the word instead of relying only on its final sound.