Tiara, molly, and maria are playing dress-up. they are all princesses and have built a castle out of cardboard boxes and colored paper. what type of play are the three girls engaging in?

They are engaged in "sociodramatic play".

Dramatic play is a type of emblematic play where a child puts on a show to go up against a part of another person, mimicking activities and discourse from prior watched circumstances. At the point when someone else winds up associated with the play, it is called sociodramatic play. 
In sociodramatic play, a child reproduces occasions or circumstances he has seen or experienced. This is unmistakable from emotional play, wherein the youngster duplicates a situation he found in films or on TV.

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