Phrases in English grammar

A phrase can consist of just one word, but usually it will contain more than one. Examples include:

• the unseen intruder
• the files that I had been examining
• the chance to clear my name
• couldn't believe
• had lost
• Quite carelessly
• about midnight
• from my fingers
• Because of this one stupid mistake

The most important point about phrases is that they do not include verbs that can change according to the time reference and in many cases they do not have a subject either. Unlike clauses, they can never stand alone as sentences.
Phrases are often classified into four basic types, taking their names from what is considered to be the class of themost important word in the phrase. There are seven word classes; these are:

• the verb
• the noun
• the adverb
• the preposition
• the adjective
• the pronoun
• the conjunction

The respective phrase types are named, unsurprisingly, the verb phrase, noun phrase, adverb phrase and prepositional phrase. The adjectival phrase and pronoun phrase are of minor interest to us here since the former usually comprises short, simple phrases like, very sad, old enough, too sudden, while the latter are used in only a small number of expressions like, they all, almost no one, I myself etc. The conjunction (words like and, but, so) is a special case in that it does not form a phrase, but helps to connect clauses into larger structures.
The class of the most important word in any phrase will decide what type of phrase it is. This important word is often referred to as the head of the phrase. In the following examples, the head word is given in bold:

• the unseen intruder
• the files that I had been examining
• the chance to clear my name
• couldn't believe
• had lost
• Quite carelessly
• about midnight
• in the blue suit
• off the table

• The first three extracts have a noun as their head word; they are all, therefore, noun phrases (from this point on I will refer to them as NP).
• In d and e the head word is a verb (believe and lost), so they are verb phrases (VP).
• Extract f is an adverb phrase (AP) with two adverbs - the second is the main adverb, while quite qualifies it.
• The last three are all prepositional phrases (PP) as they start with prepositions. 

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