How to use I-Adjectives in Japanese

How to use I-Adjectives in Japanese

An Introduction to i-Adjectives in Japanese for Beginners

Welcome to our third video and article series with tutor Naomi. In this live-stream, Naomi explains briefly how to use i-adjectives in their normal, negative and polite forms.

I-adjectives are called that way because they always end on an “i” when placed before the noun they are modifying. First, let’s take a look at two i-adjectives that are used quite frequently.
あつ
Hot
さむ
Cold
To convert i-adjectives into their polite forms, simply add “です” at the end:
あついですさむいです “です” can only be added when the adjective is placed at the end of the sentence, not when it is used to modify a noun. If you want to make a polite sentence with an i-adjective as a noun modifier, you can put “です” after the modified noun. E.g.: I-adjective as a noun modifier (polite):
今日きょうあつ天気てんきです
The weather is hot today.
I-adjective at the end of a sentence (polite)今日きょうあついです
It’s hot today.
If you would like to talk about your own sensation of the weather, you can simply add “わたしは” before the adjective, but it may send more natural not to:
わたしはあつです。
I feel hot.
わたしはさむです。
I feel cold.
If you are talking to a friend, these are more natural ways to express your sensation of the weather:
今日きょうあつね!
It’s hot today!
最近さいきんけっこうさむね。
It’s quite cold recently.
今日きょうあつくない
Isn’t it hot today?
さむのはもういやだ!
I’m done with the cold!
Now, to express the negative of an i-adjective, you replace the “い” at the end with “くない”:
あつくない
Not hot
さむくない
Not cold
Again, if your adjective is at the end of the sentence you can add “です” to make your sentence polite. If you use the adjective to modify a noun, again, please add “です” after the noun.
I-adjective as a noun modifier (polite, negative):
今日きょうさむくないです
Today is not a cold day.
I-adjective at the end of a sentence (polite, negative):
今日きょうさむくないです。
Today is not cold.
Here are a few more example sentences from Naomi’s stream:
これからさむくなりますね。
It’s going to get colder from now on.
京都きょうと今日きょうさむいです
It is cold in Kyoto today as well.
ひるあついです
It is hot at noon.
いまあつくないです
It’s not hot right now.
That’s it for today. If you have any questions, you can always clear them up by booking a lesson with one of our native Japanese tutors. See you next time!
単語たんごリスト(Vocabulary list)
形容詞けいようし I-adjective
否定文ひていぶん Negative sentence
天気てんき Weather
今日きょう Today
京都きょうと Kyoto
ひる Noon