Questions & Answers about Når jeg ikke forstår grammatikk, slår jeg opp i en ordbok.
In Norwegian, ikke (not) normally comes after the verb in main clauses, but in subordinate clauses (clauses introduced by words like når, fordi, at etc.), the word order changes.
Your first part, "Når jeg ikke forstår grammatikk", is a subordinate clause introduced by Når (when). The typical word order inside such a clause is:
Subject – (adverbs like ikke) – Verb – (objects, etc.)
So:
- jeg = subject
- ikke = negation adverb
- forstår = verb
Hence: "jeg ikke forstår" is the correct subordinate clause order. Saying "Når jeg forstår ikke grammatikk" would be wrong.