What is wrong with writing "The teachers write books"? Isn't Lærere the definite form? Is it only pointing out an english mistake or something I'm overlooking?
When I try to translate using google, both "lærere skriver bøker" and "lærerne skriver bøker" outputs "teachers write books" so I wanted to check if it was only in english but in french both translates the same answer, this time as "les enseignants écrivent des livres".
"les" being a definite plural article, I don't know if Google is just lame for Bokmål or?
The æ-sound is similar to the English short a in "hat", but in Norwegian it can be both long and short. In "lærer" you have the long version, so just hold it longer than you would in English saying "hat".
It's understandable that it's hard pronouncing -rer if you're not used to rolling r's. Try to tap the tip of your tongue against the area right above your upper front teeth inside your mouth, while pronouncing "eh", and feeling Scottish (it may help...)