The classes were all held (verb) in the morning (adverb).
Work began (verb) promptly at nine o’clock (adverb).
The students found the illustrations (noun) of the problem (adjective) interesting and helpful.
Teachers located materials (noun) on different topics (adjective).
Classes (noun) like these (adjective) kept the students busy
A prepositional phrase is a phrase that has a preposition, and the object of the preposition (a noun, pronoun, gerund, or clause) and, it may have a modifier of the object (E.g. the). A subject is never part of a prepositional phrase, and this type of phrase can work as an adjective or an adverb.
As an adverb, the prepositional phrase answers the questions How? When? or Where. And as an adjective, it answers the question Which one?
10. The classes were all held in the morning.
In: Preposition; the: modifier of the object; morning: object.
The prepositional phrase works as an adverb and it modifies the verb "held".
11. Work began promptly at nine o’clock.
At: Preposition; nine o'clock: object. The prepositional phrase works as an adverb and it modifies the verb "began"
12. The students found the illustrations of the problem interesting and helpful.
Of: Preposition; the: modifier of the object; problem: object. The prepositional phrase works as an adjective and it modifies the noun "the illustrations"
13. Teachers located materials on different topics.
On: Preposition; different topics: object. The prepositional phrase works as an adverb and it modifies the verb "located"
14. Classes like these kept the students busy.
Like: Preposition; these: object. The prepositional phrase works as an adjective and it modifies the noun "Classes".
