phrasal node (NP, PP, VP); and there are eight phrases identified by phrase structure analysis in the example sentence. On the other hand, the dependency tree identifies a phrase by any node that exerts dependency upon, or dominates, another node. And, using dependency analysis, there are six phrases in the sentence. The trees and phrase-counts demonstrate that different theories of syntax differ in the word combinations they qualify as a phrase. Here the constituency tree identifies three phrases that the dependency trees does not, namely: house at the end of the street, end of the street, and the end. More analysis, including about the plausibilities of both grammars, can be made empirically by applying constituency tests. Heads and dependents In grammatical analysis, most phrases contain a head, which identifies the type and linguistic features of the phrase. The syntactic category of the head is used to name the category of the phrase; for example, a phrase whose head is a noun is called a noun phrase. The remaining words in a phrase are called the dependents of the head. In the following phrases the head-word, or head, is bolded: too slowly — Adverb phrase (AdvP); the head is an adverb very happy — Adjective phrase (AP); the head is an adjective the massive dinosaur — Noun phrase (NP); the head is a noun (but see below for the determiner phrase analysis) at lunch — Preposition phrase (PP); the head is a preposition watch TV — Verb phrase (VP); the head is a verb The above five examples are the most common of phrase types; but, by the logic of heads and dependents, others can be routinely produced. For instance, the subordinator phrase: before that happened — Subordinator phrase (SP); the head is a subordinating conjunction—it subordinates the independent clause By linguistic analysis this is a group of words that qualifies as a phrase, and the head-word gives its syntactic name, "subordinator", to the grammatical category of the entire phrase. But this phrase, "before that happened", is more commonly classified in other grammars, including traditional English grammars, as a subordinate clause (or dependent clause); and it is then labelled not as a phrase, but as a clause. Most theories of syntax view most phrases as having a head, but some non-headed phrases are acknowledged. A phrase lacking a head is known as exocentric, and phrases with heads are endocentric. Functional categories