Dreaming in english

So I had this interesting dream last night. Have been thinking about it multiple times throughout the day, and then suddenly it hit me, that the whole dream was in english. So I started thinking about this and I'm pretty sure it's something that happens from time to time. I just thought that was kind of funny, weird, interesting. Ofcourse it makes sense, since I spend a lot of the day writing, reading, hearing english. I wonder what controls this..