Why is 高いです acceptable but 高いではあります not acceptable?


[This](https://japanese.stackexchange.com/questions/1905/when-is-it-okay-to-
use-%E3%81%82%E3%82%8A%E3%81%BE%E3%81%99-with-a-living-subject) interesting
thread got me thinking about the various forms of the copula and how `です` is a
contraction of `で（は）あります`. I am wondering why the standard X は Y で（は）あります does
not seem to work for certain words, like i-adjectives. Please correct me if I
am wrong, but I think that the following examples show what I mean:

> **(1)** これは高いです。 **O**
>
> **(2)** これは高いではあります。 **X**
>
> **(3)** 彼は元気です。 **O**
>
> **(4)** 彼は元気ではあります。 **O**

**(2)** is the only one that feels unnatural to me but I'm not sure why.




This is because an i-adjective does not require だ (or its te-form で) in the
first place. です at the end of a sentence like これは高いです is **not a copula** but
a politeness marker which never conjugates.

  * [Why should I use つかれました and not つかれたです](https://japanese.stackexchange.com/q/15300/5010):

> Usually, です is a polite copula, similar to だ but more polite. But です can
> also be a politeness marker added to adjectives. When it's a politeness
> marker, です doesn't inflect for tense.

  * [です after some verbs](https://japanese.stackexchange.com/q/35950/5010)

> In Japanese, there's no need for a verb like be to show tense on adjectives.
> Adjectives can indicate tense all on their own, using the endings -い and
> -かった. In this case, です doesn't have its usual grammatical function. Instead,
> it's functioning as a politeness marker.

Instead, you can say これは高くはあります without using だ/で at all.




This is because an i-adjective does not require だ (or its te-form で) in the
first place. です at the end of a sentence like これは高いです is **not a copula** but
a politeness marker which never conjugates.

  * [Why should I use つかれました and not つかれたです](https://japanese.stackexchange.com/q/15300/5010):

> Usually, です is a polite copula, similar to だ but more polite. But です can
> also be a politeness marker added to adjectives. When it's a politeness
> marker, です doesn't inflect for tense.

  * [です after some verbs](https://japanese.stackexchange.com/q/35950/5010)

> In Japanese, there's no need for a verb like be to show tense on adjectives.
> Adjectives can indicate tense all on their own, using the endings -い and
> -かった. In this case, です doesn't have its usual grammatical function. Instead,
> it's functioning as a politeness marker.

Instead, you can say これは高くはあります without using だ/で at all.

