Prepositional Phrases

In a sentence prepositions show the relation of one word to another word. Prepositions require an object to complete them, typically a noun or a pronoun. A preposition and its object is called a prepositional phrase. Prepositional phrases can modify nouns, verbs, phrases, and complete clauses. 

Prepositional phrases are used as adjectives or adverbs:
A prepositional phrase acts as an adjective when it modifies (describes) a noun or a pronoun. When prepositional phrases are used as adjectives, the phrase comes immediately after the noun or pronoun it modifies. The phrase answers one of the following questions about the word it modifies: Which one? What kind of? How many? Whose?

A prepositional phrase acts as an adverb when it modifies (describes) a verb. When prepositional phrases are used as adverbs, they may be found in any place in the sentence. The adverb phrase tells: How, When, Where, or Under What Condition about a Verb, Adjective, or Adverb.

Melanie eats breakfast every day in the garden.

The prepositional phrase,“in the garden,” tells where Melanie ate breakfast.
The phrase is used as an adverb modifying the noun “garden.”

My check for the book is in the mail.                     
The prepositional phrase, "for the book,” tells which check.                                                                    
The phrase is used as an adjective modifying the noun "check."

The accountant at the bank seemed nervous. 

The prepositional phrase,“at the bank,” tells what condition (nervous) about the verb seemed.  
                     
The phrase is used as an adverb modifying the verb seemed.


The following words are the most commonly used prepositions:
about                   out                         instead of             by
below                  until                       regarding             in
excepting            against                    despite                 at
off                       beyond                   because of           of
toward                outside                    through                to
above                  inside                     within
beneath               over                        down
except                 along                      without
near                    among                     before
under                  upon                       during
across                 around                    throughout
beside(s)             past                        with regard to
from                   up to                       with respect to
onto                   since                        behind
underneath         concerning               for
after                   in spite of                on
between             in front of                 like
with                   up                            into

Participial Phrases

It's a phrase that begins with a present participle (ending in-ing) or past participle (ending in -en or -ed). A participle is a type of verbal, it is a word formed from a verb that is used as an adjective to modify nouns, but functions as another part of speech. A participial phrase is made up of the participle, its modifiers, and other words needed to complete the idea begun by the participle. It commonly functions as an adjective.  

A participial phrase can be formed from relative clause, adverbial clause or a simple sentence. Besides, it can be in continuos form (being shown) or perfect form (having been shown).  

Like clauses, participial phrases can be restrictive or nonrestrictive. If the original clause is restrictive, the participial phrase formed from it will be also restrictive. Participial phrases are punctuated the same way as clauses; that is, it depends on whether the participial phrase is restrictive or nonrestrictive. A restrictive phrase is not punctuated with commas since it is necessary to correctly identify the noun phrase it modifies. However, a nonrestrictive phrase is punctuated by commas since it gives additional information about the noun it modifies. 

Working hard all year, the student finished his thesis by fall semester.  
                                            
   - Working is the participle (functioning as an adjective, describing the student).  

Stolen by the hackers, the passwords were changed at once.    
                                                         
  - Stolen is the participle (functioning as an adjective) describing the passwords.

Actors which have competed in the Grammy awards can early attend the ceremony.      
               
  - (Perfect / restrictive participial phrase) 

The books, that were being distributed in class, support students with learning difficulties.  
  - (Continuos / nonrestrictive participial phrase)