Feeling powerful is important to preschool children, and they can experience it in their imagination even if they often feel small and helpless in real life. Their pretend play is their way of trying on new roles and sorting out what's real from what's imaginary.
Words help preschoolers to feel important.
Friends are very important to preschoolers, and they will play with imaginary friends if they can't play with real ones. Although social experiences are important, don't expect their social interactions to run smoothly. Preschoolers' play with others is usually quite bumpy, and during a morning of play you will probably observe tenderness, caring, imagination, laughter, shouts, screams, foul language, cooperation, arguing, and hitting and kicking, as children go about the business of getting to know each other. So keep social gatherings such as birthday parties simple and short. One hour long and one guest for each year of age are good rules if you want everyone to have a good time.