Tu es bien tête en l'air ce matin !
I use this phrase to express the idea of "avoir la tête dans les nuages", but I have always wondered why it is coupled with "être" rather than "avoir". To see "être" used like this... it sure is bizarre. Can someone explain this grammatical construction?
On another note: I have heard French speakers say "tu as la tête en l'air" a couple of times before, but I'm not sure it is a legitimate variant.