The French think differently from the English. In English you will use the word think in various ways. For ordinary thoughts, thinking about things, the French will use penser. When negotiating and you want to think about it, the French will use réfléchir. And if you want to mention something while it's on your mind, while you are thinking about it, the French will use songer. And A Midsummer Night's Dream becomes Le Songe d'une Nuit d'été.
Hmmmmmm something to get my head around.