I need to know what the book is to answer this question.
"Everyone loves chocolate in any form". The preposition phrase in the previous written sentence is "in any form". A preposition phrase is considered as such when it includes a preposition, in this case the word "in", but also has an object and any other word that modifies the object. In the example used, the object of the preposition phrase is "form" and the word "any" works as a modifier of the object.
