です？ Wikipedia says: "word used to grammatically link a subject and predicate, often translated into English using the verb "to be". And, yes they do use it. But what is strange about it?
Do English really use "to be" (in its various conjugations)?
There's an anime character who ends every sentence with です (as I described above). GP is probably referring to a famous internet meme where that's the only word she knows.
