Shouldn't it be possible to say 'this is a book' ?
I just checked this/that usage in English, and this - is used to describe things that are near us, that - things that are far from us.
But then again - this sentence doesn't specify if a book is near or not. And I get 'wrong answer' beep quite often on those type of sentences ;(
Of course, it is possible to say "This is a book" but then the Norwegian translation would be Dette er en bok instead of Det er en bok (That/It is a book).
When det is pronounced
/ˈdeː/ (stressed) it is usually translated as "that" and when the pronunciation isn't emphasized -
/də/ (unstressed), it's translated as "it".
You're right about "this" vs. "that" usage. The same rule applies in Norwegian as well.
Click here to hear what IPA symbols sound like.
Det translates to "that, it" so both answers (That is a book./It is a book.) are equally correct.
Before a noun is introduced, the demonstrative pronoun used is always det.
Det er en bok. Den er interessant. (It is a book. It's interesting.)
Det er et insekt. Det er farlig. (It is an insect. It's dangerous.)
When you want to refer to that noun, you have to change the demonstrative pronoun according to its gender (den - masculine/feminine, det - neuter). However, this is used only to refer to animals and things, not human beings.