Final answer:
The phrase 'Josh sat between Mark and Leo' is an adjective prepositional phrase because it modifies the noun 'Josh'. However, the desire to sit beside Julie is additional information and does not form a prepositional phrase.
Step-by-step explanation:
The phrase 'Josh sat between Mark and Leo' contains a prepositional phrase that functions as an adjective prepositional phrase because it is describing Josh's position in relation to Mark and Leo, which adds detail to the noun 'Josh'. However, the second part, which expresses a desire ('but he really wanted to sit beside Julie'), is not a prepositional phrase but rather provides additional information about Josh's preference, which could be seen as modifying the verb 'sat', thus functioning adverbially, but without forming a prepositional phrase.
When analyzing sentences, it's important to note that a prepositional phrase consists of a preposition and its object, and it can function adjectivally—to describe a noun—or adverbially—to modify a verb, an adjective, or another adverb. The difference between how these phrases function lies in what they are modifying within the sentence. In the sentence provided by the student, the first part is clearly adjectival. There is an absence of a phrase fulfilling the role of subject complement with a preposition in this example.