FYI: The terminology around those two concepts are pretty iffy. What are called 形容動詞 (adjectival verbs) are sometimes called “adjectival nouns” in English, and 形容詞 (adjectives) are sometimes referred to as “adjectival verbs.”
To summarize, keiyoudoushi work similarly to nouns, whereas keiyoushi work kind of like adjectives. This is in regards to which endings you put on them and when.
Keiyoushi are “i-adjectives” and keiyoudoushi are “na-adjectives” in Genki-speak.
I often hear that Japanese language learners use the word いadjectives for Keiyoushi (形容詞) and なadjectives for Keiyioudoushi (形容動詞).
The dictionary forms of Keiyoushi end with the word い like 美しい(うつくしい/beautiful), かわいい(cute), 優しい(やさしい/kind or sweet), or 暑い(あつい/hot).
You can use them alone and with nouns as adjectives.
彼女は美しいです。 かのじょ は うつくしい です。 She is beautiful.
私はかわいいぬいぐるみが好きです。 I like cute plushies.
今日は暑いです。 きょう は あつい です。 It’s hot today.
As for their past tense form, it’s 美しかった(うつくしかった), かわいかった, or 暑かった(あつかった).
You just remove their い at the end and put かった instead.
昨日は暑かった(です)。 きのう は あつかった です。 It was hot yesterday.
When you put them before nouns you don’t have to change their form to the past tense one. You just change です or だ to でした or だった.
私は昔、かわいいぬいぐるみが好きでした。 わたし は むかし かわいい ぬいぐるみ が すき でした。 I used to like cute plushies.
The Dictionary forms of Keiyoudoushi end だ, but when it’s put before a noun, they change it to な like 綺麗な(きれいな/beautiful ＋nouns), 安全な(あんぜんな/safe or secure ＋nouns), 完璧な(かんぺきな/perfect ＋nouns).
この綺麗な花の名前は何ですか？ この きれいな はな の なまえ は なんですか？ What is this beautiful flower’s name?
You can use them alone as adjectives though.
この部屋は綺麗だ。 このへや は きれいだ。 This room is clean.
As for the past tense form, you just change だ to だった like 綺麗だった(きれいだった).
あの部屋は安全だった。 あの へや は あんぜんだった。 That room was secure.
When you put them before nouns you don’t have to change their form to the past tense one. You just change です or だ to でした or だった.
Massive simpification but it might give you handholds:
There are two basic sentence patterns in Japanese (Verbs, and noun+copula). Both are complete thoughts and complete sentences which can of course be extended/modified with attachment glue like WA, GA, WO.
Any complete sentence can attach before a noun to modify it.
-i adjective are verbs, complete sentences and complete thoughts. As verbs we can just throw them before any noun to modify it.
NA adjectives are nouns and that NA is a shortened version of the copula (DA) that turn the phrase into a verb (complete thought/sentence) in the form (NA adjective+ DA/NA) which then can do what other verbs do: stand as complete sentences, be put before nouns to modify them etc.
This is not a complete description of all Japanese grammar but it is a surprisingly extensible crutch, and almost every complicated sentence can be reduced to a simple sentence of on of those two forms, with a bunch of stuff tacked to it.
Once you start building from this base you can pretty easily at least figure out the scaffolding of a sentence.
4 comments
You use them to describe things.
FYI: The terminology around those two concepts are pretty iffy. What are called 形容動詞 (adjectival verbs) are sometimes called “adjectival nouns” in English, and 形容詞 (adjectives) are sometimes referred to as “adjectival verbs.”
To summarize, keiyoudoushi work similarly to nouns, whereas keiyoushi work kind of like adjectives. This is in regards to which endings you put on them and when.
Keiyoushi are “i-adjectives” and keiyoudoushi are “na-adjectives” in Genki-speak.
I often hear that Japanese language learners use the word いadjectives for Keiyoushi (形容詞) and なadjectives for Keiyioudoushi (形容動詞).
The dictionary forms of Keiyoushi end with the word い like 美しい(うつくしい/beautiful), かわいい(cute), 優しい(やさしい/kind or sweet), or 暑い(あつい/hot).
You can use them alone and with nouns as adjectives.
彼女は美しいです。
かのじょ は うつくしい です。
She is beautiful.
私はかわいいぬいぐるみが好きです。
I like cute plushies.
今日は暑いです。
きょう は あつい です。
It’s hot today.
As for their past tense form, it’s 美しかった(うつくしかった), かわいかった, or 暑かった(あつかった).
You just remove their い at the end and put かった instead.
昨日は暑かった(です)。
きのう は あつかった です。
It was hot yesterday.
When you put them before nouns you don’t have to change their form to the past tense one.
You just change です or だ to でした or だった.
私は昔、かわいいぬいぐるみが好きでした。
わたし は むかし かわいい ぬいぐるみ が すき でした。
I used to like cute plushies.
The Dictionary forms of Keiyoudoushi end だ, but when it’s put before a noun, they change it to な like 綺麗な(きれいな/beautiful ＋nouns), 安全な(あんぜんな/safe or secure ＋nouns), 完璧な(かんぺきな/perfect ＋nouns).
この綺麗な花の名前は何ですか？
この きれいな はな の なまえ は なんですか？
What is this beautiful flower’s name?
You can use them alone as adjectives though.
この部屋は綺麗だ。
このへや は きれいだ。
This room is clean.
As for the past tense form, you just change だ to だった like 綺麗だった(きれいだった).
あの部屋は安全だった。
あの へや は あんぜんだった。
That room was secure.
When you put them before nouns you don’t have to change their form to the past tense one.
You just change です or だ to でした or だった.
あの公園にあった花は本当に綺麗な花だった。
あの こうえん に あった はな は ほんとう に きれいな はな だった。
Massive simpification but it might give you handholds:
There are two basic sentence patterns in Japanese (Verbs, and noun+copula). Both are complete thoughts and complete sentences which can of course be extended/modified with attachment glue like WA, GA, WO.
Any complete sentence can attach before a noun to modify it.
-i adjective are verbs, complete sentences and complete thoughts. As verbs we can just throw them before any noun to modify it.
NA adjectives are nouns and that NA is a shortened version of the copula (DA) that turn the phrase into a verb (complete thought/sentence) in the form (NA adjective+ DA/NA) which then can do what other verbs do: stand as complete sentences, be put before nouns to modify them etc.
This is not a complete description of all Japanese grammar but it is a surprisingly extensible crutch, and almost every complicated sentence can be reduced to a simple sentence of on of those two forms, with a bunch of stuff tacked to it.
Once you start building from this base you can pretty easily at least figure out the scaffolding of a sentence.