A phrase is a group of words that lacks a subject or a predicate or both.

Noun phrases

Made up of a noun and all its modifiers, a noun phrase can function in a sentence as a subject, object, or complement.

Verb phrases

A main verb and its auxiliary verbs make up a verb phrase, which can function in a sentence only as a verb.

Frank can swim for a long time.

His headaches might have been caused by tension.

Prepositional phrases

A prepositional phrase begins with a preposition and includes a noun or pronoun (the object of the preposition) and any modifiers of the object. Prepositional phrases usually function as adjectives or adverbs.

Verbal phrases

Verbals look like verbs, but they function as nouns, adjectives, or adverbs. There are three kinds of verbals: participles, gerunds, and infinitives.

Participles and participial phrases

The present participle is the -ing form of a verb (spinning). The past participle of most verbs ends in -ed (accepted), but some verbs have an irregular past participle (worn, frozen). Participles function as adjectives (42a).

Participial phrases, which also act as adjectives, consist of a present or past participle and any modifiers, objects, or complements.

Gerunds and gerund phrases

The gerund has the same -ing form as the present participle but functions as a noun.

Gerund phrases, which function as nouns, consist of a gerund and any modifiers, objects, or complements.

Infinitives and infinitive phrases

The infinitive is the to form of a verb (to dream, to be). An infinitive can function as a noun, an adjective, or an adverb.

Infinitive phrases consist of an infinitive and any modifiers, objects, or complements. Like infinitives, they function as nouns, adjectives, or adverbs.

Absolute phrases

An absolute phrase usually includes a noun or pronoun and a participle. It modifies an entire sentence rather than a particular word and is usually set off from the rest of the sentence with commas (54d).

I stood on the deck, the wind whipping my hair.

My fears laid to rest, I set off on my first solo flight.

When the participle is being, it is often omitted.

The ambassador, her head [being] high, walked out of the room.

Appositive phrases

An appositive phrase is a noun phrase that renames the noun or pronoun that immediately precedes it (54d).

The report, a hefty three-volume work, included more than ninety recommendations.

We had a single desire, to change the administration’s policies.