Page 124 - Just Enough English Grammar Illustrated Book

6.4 Single-Word and Compound Prepositions
Prepositions can take the form of a single word. At, in, out,
and for are some examples of single-word prepositions.
Multiple-word prepositions are called compound prepositions.
Out of, in front of, and across from are examples of
prepositions that are composed of more than a single word.

6.5 Prepositional Phrases with Nouns and Pronouns

A prepositional phrase consists of two distinct parts. The first
part is the preposition itself. The second part, which follows
the preposition, is a noun or pronoun that is called the object
of the preposition. Together, these two parts form what is called
a prepositional phrase.

Prepositional Phrases with Nouns

Example:
Susan swims with Jake.

Preposition Object (Noun)
with Jake = prepositional phrase

In this example, with Jake is a prepositional phrase. The
preposition with is a single-word preposition. It is followed
by the noun Jake. Jake is called the object of the preposition.
A noun does not change in form when it becomes an object
of a preposition.

A preposition and the object of the preposition
form a prepositional phrase.

Example:
The balls are on top of the locker.

Preposition Object (Noun)
on top of the locker = prepositional phrase
The preposition on top of is a compound preposition composed
of three words. The noun locker represents the object of the
preposition. By combining the preposition on top of with the
object noun the locker, you form a prepositional phrase.
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