A participle is a verbal that is used as an adjective and most often ends in -ing or -ed. The term verbal indicates that a participle, like the other two kinds of verbals, is based on a verb and therefore expresses action or a state of being. However, since they function as adjectives, participles modify nouns or pronouns. There are two types of participles: present participles and past participles. Present participles end in -ing. Past participles end in -ed, -en, -d, -t, -n, or -ne as in the words asked, eaten, saved, dealt, seen, and gone.

• The crying baby had a wet diaper.
• Shaken, he walked away from the wrecked car.
• The burning log fell off the fire.
• Smiling, she hugged the panting dog.

A participial phrase is a group of words consisting of a participle and the modifier(s) and/or (pro)noun(s) or noun phrase(s) that function as the direct object(s), indirect object(s), or complement(s) of the action or state expressed in the participle, such as:

The participial phrase functions as an adjective modifying Jack.
Removing (participle)
his coat (direct object of action expressed in participle)

The participial phrase functions as an adjective modifying cousin.
walking (participle)
along the shoreline (prepositional phrase as adverb)

The participial phrase functions as an adjective modifying children.
interested (in) (participle)
music (direct object of action expressed in participle)
early (adverb)

The participial phrase functions as an adjective modifying Lynn.
Having been (participle)
a gymnast (subject complement for Lynn, via state of being expressed in participle)

Placement: In order to prevent confusion, a participial phrase must be placed as close to the noun it modifies as possible, and the noun must be clearly stated.

• Carrying a heavy pile of books, his foot caught on a step. *
• Carrying a heavy pile of books, he caught his foot on a step.

In the first sentence, there is no clear indication of who or what is performing the action expressed in the participle carrying. Certainly, foot can't be logically understood to function in this way. This situation is an example of a dangling modifier error, since the modifier (the participial phrase) is not modifying any specific noun in the sentence and is thus left "dangling." Since a person must be doing the carrying for the sentence to make sense, a noun or pronoun that refers to a person must be in the place immediately after the participial phrase, as in the second sentence.

Punctuation: When a participial phrase begins a sentence, a comma should be placed after the phrase.

• Arriving at the store, I found that it was closed.
• Washing and polishing the car, Frank developed sore muscles.

If the participle or participial phrase comes in the middle of a sentence, it should be set off with commas only if the information is not essential to the meaning of the sentence.

• Sid, watching an old movie, drifted in and out of sleep.
• The church, destroyed by a fire, was never rebuilt.

Note that if the participial phrase is essential to the meaning of the sentence, no commas should be used:

• The student earning the highest grade point average will receive a special award.
• The guy wearing the chicken costume is my cousin.

If a participial phrase comes at the end of a sentence, a comma usually precedes the phrase if it modifies an earlier word in the sentence but not if the phrase directly follows the word it modifies.

• The local residents often saw Ken wandering through the streets.
  (The phrase modifies Ken, not residents.)
• Tom nervously watched the woman, alarmed by her silence.
  (The phrase modifies Tom, not woman.)

Points to remember

1. A participle is a verbal ending in -ing (present) or -ed, -en, -d, -t, -n, or -ne (past) that functions as an adjective, modifying a noun or pronoun.
2. A participial phrase consists of a participle plus modifier(s), object(s), and/or complement(s).
3. Participles and participial phrases must be placed as close to the nouns or pronouns they modify as possible, and those nouns or pronouns must be clearly stated.
4. A participial phrase is set off with commas when it:
   • a) comes at the beginning of a sentence
   • b) interrupts a sentence as a nonessential element
   • c) comes at the end of a sentence and is separated from the word it modifies.