I have a question about sentence structure. I found a sentence like this,
Wenn Sie es wissen muessen, so erkläre ich Ihnen, dass ich einen Besuch gehabt habe.
My question is about the first clause. If I were to write
"You must know it", I would say "Sie müssen es wissen". Why then does it become "wissen müssen" when I say "If you must know it ..." ?