よう - Nayou & Noyou


For よう, why do we prepend な for Na-adjectives, and の for regular nouns? Is
there a logical understanding behind this from like a Japanese perspective? I
feel as though since they're both technically nouns, then we should treat them
the same.




よう is basically a na-adjective which can also behave as a noun.

Note that not all na-adjectives can be used as nouns, but some can. That's why
they fall under the category of adjectival nouns: no-adjectives and na-
adjectives, using の and な respectively.

* * *

## よう as a noun

After **nouns** + no:

  * 彼は **留守** のようでした。

After **adjectival** nouns + na/no in the non-past affirmative context:

  * 彼は **大丈夫** なようです。 大丈夫 is a na-adjective, which is modifying よう, a noun.
  * 彼は **病気** のようだ。病気 is a no-adjective, which is modifying よう, a noun.

After **adjectival** nouns or **nouns** + じゃない, だった or じゃなかった in the past
context:

  * 彼は練習が **嫌** だったようです。The clause 彼は練習が嫌だった modifies よう, a noun.

## よう as a na-adjective

Once よう has been modified, this noun can also modify another noun. To do this,
な is used.

  * この間食べたようなケーキだよ。この間食べた modifies よう, and よう modifies ケーキ by using な.

Just like a na-adjective, it can be followed by に to form an adverb.

  * 彼女はまるで魚のように速く泳げます。魚 modifies よう, and ように creates an adverb to modify 速く泳げます.

