In linguistics, syntax is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure (constituency), agreement, the nature of crosslinguistic variation, and the relationship between form and meaning (semantics). There are numerous approaches to syntax that differ in their central assumptions and goals.
A syntactic category is a syntactic unit that theories of syntax assume. Word classes, largely corresponding to traditional parts of speech, are syntactic categories. In phrase structure grammars, the phrasal categories are also syntactic categories. Dependency grammars, however, do not acknowledge phrasal categories.
In grammar, a phrase—called expression in some contexts—is a group of words or singular word acting as a grammatical unit. For instance, the English expression "the very happy squirrel" is a noun phrase which contains the adjective phrase "very happy". Phrases can consist of a single word or a complete sentence. In theoretical linguistics, phrases are often analyzed as units of syntactic structure such as a constituent.
Phrase structure rules are a type of rewrite rule used to describe a given language's syntax and are closely associated with the early stages of transformational grammar, proposed by Noam Chomsky in 1957. They are used to break down a natural language sentence into its constituent parts, also known as syntactic categories, including both lexical categories and phrasal categories. A grammar that uses phrase structure rules is a type of phrase structure grammar. Phrase structure rules as they are commonly employed operate according to the constituency relation, and a grammar that employs phrase structure rules is therefore a constituency grammar; as such, it stands in contrast to dependency grammars, which are based on the dependency relation.
A noun phrase, or nominal (phrase), is a phrase that has a noun or pronoun as its head or performs the same grammatical function as a noun. Noun phrases are very common cross-linguistically, and they may be the most frequently occurring phrase type.
An adjective phrase is a phrase whose head is an adjective. Almost any grammar or syntax textbook or dictionary of linguistics terminology defines the adjective phrase in a similar way, e.g. Kesner Bland (1996:499), Crystal (1996:9), Greenbaum (1996:288ff.), Haegeman and Guéron (1999:70f.), Brinton (2000:172f.), Jurafsky and Martin (2000:362). The adjective can initiate the phrase, conclude the phrase, or appear in a medial position. The dependents of the head adjective—i.e. the other words and phrases inside the adjective phrase—are typically adverb or prepositional phrases, but they can also be clauses. Adjectives and adjective phrases function in two basic ways, attributively or predicatively. An attributive adjective (phrase) precedes the noun of a noun phrase. A predicative adjective (phrase) follows a linking verb and serves to describe the preceding subject, e.g. The man is very happy.
A parse tree or parsing tree or derivation tree or concrete syntax tree is an ordered, rooted tree that represents the syntactic structure of a string according to some context-free grammar. The term parse tree itself is used primarily in computational linguistics; in theoretical syntax, the term syntax tree is more common.
In linguistics, a determiner phrase (DP) is a type of phrase headed by a determiner such as many. Controversially, many approaches, take a phrase like not very many apples to be a DP, headed, in this case, by the determiner many. This is called the DP analysis or the DP hypothesis. Others reject this analysis in favor of the more traditional NP analysis where apples would be the head of the phrase in which the DP not very many is merely a dependent. Thus, there are competing analyses concerning heads and dependents in nominal groups. The DP analysis developed in the late 1970s and early 1980s, and it is the majority view in generative grammar today.
A language is head-marking if the grammatical marks showing agreement between different words of a phrase tend to be placed on the heads of phrases, rather than on the modifiers or dependents. Many languages employ both head-marking and dependent-marking, and some languages double up and are thus double-marking. The concept of head/dependent-marking was proposed by Johanna Nichols in 1986 and has come to be widely used as a basic category in linguistic typology.
A dependent-marking language has grammatical markers of agreement and case government between the words of phrases that tend to appear more on dependents than on heads. The distinction between head-marking and dependent-marking was first explored by Johanna Nichols in 1986, and has since become a central criterion in language typology in which languages are classified according to whether they are more head-marking or dependent-marking. Many languages employ both head and dependent-marking, but some employ double-marking, and yet others employ zero-marking. However, it is not clear that the head of a clause has anything to do with the head of a noun phrase, or even what the head of a clause is.
In linguistics, branching refers to the shape of the parse trees that represent the structure of sentences. Assuming that the language is being written or transcribed from left to right, parse trees that grow down and to the right are right-branching, and parse trees that grow down and to the left are left-branching. The direction of branching reflects the position of heads in phrases, and in this regard, right-branching structures are head-initial, whereas left-branching structures are head-final. English has both right-branching (head-initial) and left-branching (head-final) structures, although it is more right-branching than left-branching. Some languages such as Japanese and Turkish are almost fully left-branching (head-final). Some languages are mostly right-branching (head-initial).
Dependency grammar (DG) is a class of modern grammatical theories that are all based on the dependency relation and that can be traced back primarily to the work of Lucien Tesnière. Dependency is the notion that linguistic units, e.g. words, are connected to each other by directed links. The (finite) verb is taken to be the structural center of clause structure. All other syntactic units (words) are either directly or indirectly connected to the verb in terms of the directed links, which are called dependencies. Dependency grammar differs from phrase structure grammar in that while it can identify phrases it tends to overlook phrasal nodes. A dependency structure is determined by the relation between a word and its dependents. Dependency structures are flatter than phrase structures in part because they lack a finite verb phrase constituent, and they are thus well suited for the analysis of languages with free word order, such as Czech or Warlpiri.
The term phrase structure grammar was originally introduced by Noam Chomsky as the term for grammar studied previously by Emil Post and Axel Thue. Some authors, however, reserve the term for more restricted grammars in the Chomsky hierarchy: context-sensitive grammars or context-free grammars. In a broader sense, phrase structure grammars are also known as constituency grammars. The defining trait of phrase structure grammars is thus their adherence to the constituency relation, as opposed to the dependency relation of dependency grammars.
A sentence diagram is a pictorial representation of the grammatical structure of a sentence. The term "sentence diagram" is used more when teaching written language, where sentences are diagrammed. The model shows the relations between words and the nature of sentence structure and can be used as a tool to help recognize which potential sentences are actual sentences.
An adpositional phrase is a syntactic category that includes prepositional phrases, postpositional phrases, and circumpositional phrases. Adpositional phrases contain an adposition as head and usually a complement such as a noun phrase. Language syntax treats adpositional phrases as units that act as arguments or adjuncts. Prepositional and postpositional phrases differ by the order of the words used. Languages that are primarily head-initial such as English predominantly use prepositional phrases whereas head-final languages predominantly employ postpositional phrases. Many languages have both types, as well as circumpositional phrases.
In theoretical linguistics, a distinction is made between endocentric and exocentric constructions. A grammatical construction is said to be endocentric if it fulfils the same linguistic function as one of its parts, and exocentric if it does not. The distinction reaches back at least to Bloomfield's work of the 1930s, who based it on terms by Pāṇini and Patañjali in Sanskrit grammar. Such a distinction is possible only in phrase structure grammars, since in dependency grammars all constructions are necessarily endocentric.
Lucien Tesnière was a prominent and influential French linguist. He was born in Mont-Saint-Aignan on May 13, 1893. As a senior lecturer at the University of Strasbourg (1924) and later professor at the University of Montpellier (1937), he published many papers and books on Slavic languages. However, his importance in the history of linguistics is based mainly on his development of an approach to the syntax of natural languages that would become known as dependency grammar. He presented his theory in his book Éléments de syntaxe structurale, published posthumously in 1959. In the book he proposes a sophisticated formalization of syntactic structures, supported by many examples from a diversity of languages. Tesnière died in Montpellier on December 6, 1954.
In linguistics, head directionality is a proposed parameter that classifies languages according to whether they are head-initial or head-final. The head is the element that determines the category of a phrase: for example, in a verb phrase, the head is a verb. Therefore, head initial would be "VO" languages and head final would be "OV" languages.
In linguistics, subordination is a principle of the hierarchical organization of linguistic units. While the principle is applicable in semantics, morphology, and phonology, most work in linguistics employs the term "subordination" in the context of syntax, and that is the context in which it is considered here. The syntactic units of sentences are often either subordinate or coordinate to each other. Hence an understanding of subordination is promoted by an understanding of coordination, and vice versa.
English adjectives form a large open category of words in English which, semantically, tend to denote properties such as size, colour, mood, quality, age, etc. with such members as other, big, new, good, different, Cuban, sure, important, and right. Adjectives head adjective phrases, and the most typical members function as modifiers in noun phrases. Most adjectives either inflect for grade or combine with more and most to form comparatives and superlatives. They are characteristically modifiable by very. A large number of the most typical members combine with the suffix -ly to form adverbs. Most adjectives function as complements in verb phrases, and some license complements of their own.
