Usage of nan desu?


In a few songs I've heard recently I've noticed that _なんです（nan desu）_ (without
the か) has been used in what seems to be maybe a declarative or emphatic sense
(not really sure), is this possible?

I'm not overly familiar with usage of _nan desu_ outside of it being used in
the question sense (i.e. _なんですか nan desu ka_ ). If someone could clarify uses
of _nan desu_ I would be super appreciative.




There is なのです (often contracted to なんです), which fits the bill. Just like you
suspect, it is declarative/emphatic.

This なんです is unrelated to 何{なん}です, but rather a combination of な (the
inflection of the copula だ, if you like), the nominalizer の plus the
"politifier" です.

It also exists in non-polite form: なのだ・なんだ.

It really appears everywhere, e.g. as a conjunction なので or question marker
～なんですか. (Again, unrelated to 何.)




There is なのです (often contracted to なんです), which fits the bill. Just like you
suspect, it is declarative/emphatic.

This なんです is unrelated to 何{なん}です, but rather a combination of な (the
inflection of the copula だ, if you like), the nominalizer の plus the
"politifier" です.

It also exists in non-polite form: なのだ・なんだ.

It really appears everywhere, e.g. as a conjunction なので or question marker
～なんですか. (Again, unrelated to 何.)

