"Cheese" and other words...

Lately we've been getting more and more frustrated with Miriam's lack of vocab as we struggle mightily to know what she wants. She does say words but sometimes for only a little while or are totally non helpful. Her first word besides mama and dada was dog but then she hasn't said that for a long time. She has said a lot of animal names- cat, bird. Some that come around more often have been Thank you, hello/hi, the classic yeah, and no. When I got pregnant she started saying baby all the time and now calls him that still though I think she is also saying Aaron too. Sometimes she 'read' her books and in one, The Maestro Plays she has added the word bravo though it sounds like baaba. Then yesterday in particular she would get a hold of the camera open the viewing screen and say cheese, cheese. I'm not sure where she picked that up because Eric and I don't really say that. So very cute in her speech yet hoping for more helpful words soon.