I walked to the shop
The prepositional phrase is "off of his skateboard" but the compound preposition "off of" is poor English. You need only use the word OFF as a preposition instead of an adverb and say he "fell off his skateboard" which means exactly the same thing.
you use a preposition usally at the end of a sentence.
Here is preposition used in a sentence. Adverb phrases use a preposition to tell what, when and how an action can occur.
of is a preposition. off is the opposite of on.
Nouns, pronouns, gerunds, and noun phrases can commonly stand after a preposition in a sentence.
There is a ball under the bed.
We might see you after the movie.
One is the preposition "with" -- "I agree with the proposal." But it could also be "to" -- "I agree to the proposal."
no it depends on if there is a prepositional phrase
There is no preposition in that sentence. The aeroplane flew in the sky. 'In' is a preposition in this sentence
In the sentence "Who asked for the textbook?," the preposition is the word FOR. Who is not a preposition; it is a pronoun.