Can every noun be a na-adjective?


I know that na-adjectives are nouns which can also act like adjectives by
affixing themselves to nouns, but can every noun do this simply by adding な or
can only certain nouns have the property of being adjectival?

For 利口 can act as a noun:

利口 n. intelligence

but can also be an adjective:

利口 an. intelligent, smart, clever, etc.




Not every noun can be a na-adjective.

* * *

A few examples of na-adjectives:

> **親切な** 人 -- kind person  
>  **安全な** 国 -- safe country  
>  **きれいな** 人 -- beautiful person  
>  **さわやかな** 風 -- refreshing breeze  
>  **ロマンチックな** 映画 -- romantic movie  
>  **健康的な** 食生活 -- healthy diet

Some nouns take の instead of な, and some categorize them as no-adjectives.
You'd say:

> **病気の** 人 -- sick person  
>  **最後の** 晩餐 -- the last supper  
>  **年配の** 女性 -- elderly woman  
>  **初期の** 肺癌 -- early lung cancer  
>  **灰色の** 空 -- gray sky

... rather than 「病気 **な** 人」「最後 **な** 晩餐」「年配 **な** 女性」「初期 **な** 肺癌」「灰色 **な**
空」.

* * *

In phrases like 「 **私の** 本」(my book) 「 **家の** 屋根」(roof of a house) 「 **日本の**
文化」(Japan's culture) 「 **空の** 色」(color of the sky), however, 「私の」「家の」「日本の」「空の」
wouldn't be considered as no-adjectives. These phrases would be considered as
"noun¹ + case particle の + noun²" ("noun² + of + noun¹") rather than "no-
adjective + noun" ("~~ _ish_ + noun").

And, you don't say 「 **私な** 本」「 **家な** 屋根」「 **日本な** 文化」「 **空な** 色」 etc. These
nouns express もの・こと rather than 状態・感情, and cannot be na-adjectives.

* * *

By the way...

> I know that na-adjectives are nouns which can also act like adjectives...

Not all na-adjectives are nouns, eg きれい, さわやか, 静か, 明らか, ロマンチック, ～～的(健康的, 劇的,
科学的 etc.)

* * *

As a side note:

You'd use "noun+な" before some words or phrases, even though the noun is not a
na-adjective. In such cases the な is the 連体形 (attributive form) of the 断定の助動詞
(assertive auxiliary) or copula だ (source: 明鏡国語辞典). Some examples from the
dictionary:

> Words that mainly take "noun+な":  
>  だけだ -- 「年が一つ **下なだけだ** 」  
>  だけに -- 「相手が **子供なだけに** 対応が難しい」  
>  ので -- 「まだ **子供なので** 理解できない」  
>  のに -- 「 **小学生なのに** よくやった」  
>  ものか(終助詞) -- 「彼が **犯人なものか** 」  
>  もので -- 「まだ **学生なもので** 」
>
> Words that take either "noun+な" or "noun+の" depending on the meaning:  
>  あまり・上・くせに・せい・ため・つもり・はず・ようだ・わけ・わり…

So you can say 「 **子供な** ので」「 **小学生な** のに」「 **形容詞な** わけではない」 etc. but it
doesn't mean 子供, 小学生, 形容詞 are na-adjectives.




Not every noun can be a na-adjective.

* * *

A few examples of na-adjectives:

> **親切な** 人 -- kind person  
>  **安全な** 国 -- safe country  
>  **きれいな** 人 -- beautiful person  
>  **さわやかな** 風 -- refreshing breeze  
>  **ロマンチックな** 映画 -- romantic movie  
>  **健康的な** 食生活 -- healthy diet

Some nouns take の instead of な, and some categorize them as no-adjectives.
You'd say:

> **病気の** 人 -- sick person  
>  **最後の** 晩餐 -- the last supper  
>  **年配の** 女性 -- elderly woman  
>  **初期の** 肺癌 -- early lung cancer  
>  **灰色の** 空 -- gray sky

... rather than 「病気 **な** 人」「最後 **な** 晩餐」「年配 **な** 女性」「初期 **な** 肺癌」「灰色 **な**
空」.

* * *

In phrases like 「 **私の** 本」(my book) 「 **家の** 屋根」(roof of a house) 「 **日本の**
文化」(Japan's culture) 「 **空の** 色」(color of the sky), however, 「私の」「家の」「日本の」「空の」
wouldn't be considered as no-adjectives. These phrases would be considered as
"noun¹ + case particle の + noun²" ("noun² + of + noun¹") rather than "no-
adjective + noun" ("~~ _ish_ + noun").

And, you don't say 「 **私な** 本」「 **家な** 屋根」「 **日本な** 文化」「 **空な** 色」 etc. These
nouns express もの・こと rather than 状態・感情, and cannot be na-adjectives.

* * *

By the way...

> I know that na-adjectives are nouns which can also act like adjectives...

Not all na-adjectives are nouns, eg きれい, さわやか, 静か, 明らか, ロマンチック, ～～的(健康的, 劇的,
科学的 etc.)

* * *

As a side note:

You'd use "noun+な" before some words or phrases, even though the noun is not a
na-adjective. In such cases the な is the 連体形 (attributive form) of the 断定の助動詞
(assertive auxiliary) or copula だ (source: 明鏡国語辞典). Some examples from the
dictionary:

> Words that mainly take "noun+な":  
>  だけだ -- 「年が一つ **下なだけだ** 」  
>  だけに -- 「相手が **子供なだけに** 対応が難しい」  
>  ので -- 「まだ **子供なので** 理解できない」  
>  のに -- 「 **小学生なのに** よくやった」  
>  ものか(終助詞) -- 「彼が **犯人なものか** 」  
>  もので -- 「まだ **学生なもので** 」
>
> Words that take either "noun+な" or "noun+の" depending on the meaning:  
>  あまり・上・くせに・せい・ため・つもり・はず・ようだ・わけ・わり…

So you can say 「 **子供な** ので」「 **小学生な** のに」「 **形容詞な** わけではない」 etc. but it
doesn't mean 子供, 小学生, 形容詞 are na-adjectives.

