Laurel really enjoys playing with the doors in my parents' house, so we recently taught her to knock on closed doors. Last week she started trying to open the refrigerator door, which seems to be an indicator of her being thirsty. (So far it seems pretty accurate, though she does say "milk," "juice," and "cup" pretty consistently.) Today she used a new phrase about the doors: "open door!" to my mother after she closed the bathroom door. It should be interesting to see what she comes up with next.