"The little girl, wearing the red checkered dress, hid in the corner during the game of hide and seek."
A participial phrase is groups of words that contains a present or past participle and modifiers, objects, and complements. It functions as an adjective.
The participial phrase functions as an adjective modifying "the little girl"
Wearing = participial
the red checkered dress = modifier
Another example of a participial phrase:
Students planning to study nursing must first meet with the dean.
The participial phrase functions as an adjective modifying "students."