Вставте слова how, why, where, what, which, whose, when, who 1)i

I dont know whose book it is, but it is not mine. Я не знаю, чья это книжка, но это не мое.

I didnt know whose book it was, but it was not mine. (Past Indefinite).

Dont I know whose book it is?

Who doesnt know whose book is it?

Whose book is it?

Dont I or did you know whose book it is?

Dont I know whose book or pen it is?

I dont know whose book it is, but it is not mine, do I?