Syntactic category in the context of "Adpositional phrase"

In grammar, a part of speech or part-of-speech (abbreviated as POS or PoS, also known as word class or grammatical category) is a category of words (or, more generally, of lexical items) that have similar grammatical properties. Words that are assigned to the same part of speech generally display similar syntactic behavior (they play similar roles within the grammatical structure of sentences), sometimes similar morphological behavior in that they undergo inflection for similar properties and even similar semantic behavior. Commonly listed English parts of speech are noun, verb, adjective, adverb, pronoun, preposition, conjunction, interjection, numeral, article, and determiner.

Other terms than part of speech—particularly in modern linguistic classifications, which often make more precise distinctions than the traditional scheme does—include word class, lexical class, and lexical category. Some authors restrict the term lexical category to refer only to a particular type of syntactic category; for them the term excludes those parts of speech that are considered to be function words, such as pronouns. The term form class is also used, although this has various conflicting definitions. Word classes may be classified as open or closed: open classes (typically including nouns, verbs and adjectives) acquire new members constantly, while closed classes (such as pronouns and conjunctions) acquire new members infrequently, if at all.

In linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns and adjectives, and verb endings, which form the conjugation of verbs.

Suffixes can carry grammatical information (inflectional endings) or lexical information (derivational/lexical suffixes). Inflection changes the grammatical properties of a word within its syntactic category. Derivational suffixes fall into two categories: class-changing derivation and class-maintaining derivation.

In linguistics, a grammatical category or grammatical feature is a property of items within the grammar of a language. Within each category there are two or more possible values (sometimes called grammemes), which are normally mutually exclusive. Frequently encountered grammatical categories include:

• Case, varying according to the relations between the participants in an action (e.g. subject, object, possession, direction, accompaniment etc.).
• Noun classes, such as gender, animacy, and so on.
• Number, varying according to the number of things (e.g. singular or plural).
• Tense, varying according to when an action takes place (e.g. present, past or future).
• Aspect, varying according to the state of an action in relation to time (e.g. completed, ongoing, repeated, habitual etc.).
• Mood and modality, varying according to the speaker's attitude towards an action and its relation to reality (e.g. statement of fact, hypothetical, questioning, ordering, suggesting etc.).
• Voice, varying according to the role taken by each participant in an action (e.g. active or passive).

Although the use of terms varies from author to author, a distinction should be made between grammatical categories and lexical categories. Lexical categories (considered syntactic categories) largely correspond to the parts of speech of traditional grammar, and refer to nouns, adjectives, etc.

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 (parts of speech) 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.

In linguistics, an argument is an expression that helps complete the meaning of a predicate, the latter referring in this context to a main verb and its auxiliaries. In this regard, the complement is a closely related concept. Most predicates take one, two, or three arguments. A predicate and its arguments form a predicate-argument structure. The discussion of predicates and arguments is associated most with (content) verbs and noun phrases (NPs), although other syntactic categories can also be construed as predicates and as arguments. Arguments must be distinguished from adjuncts. While a predicate needs its arguments to complete its meaning, the adjuncts that appear with a predicate are optional; they are not necessary to complete the meaning of the predicate. Most theories of syntax and semantics acknowledge arguments and adjuncts, although the terminology varies, and the distinction is generally believed to exist in all languages. Dependency grammars sometimes call arguments actants, following Lucien Tesnière (1959).

The area of grammar that explores the nature of predicates, their arguments, and adjuncts is called valency theory. Predicates have a valence; they determine the number and type of arguments that can or must appear in their environment. The valence of predicates is also investigated in terms of subcategorization.

In linguistics, X-bar theory is a model of phrase structure and a theory of syntactic category formation that proposes a universal schema for how phrases are organized. It suggests that all phrases share a common underlying structure, regardless of their specific category (noun phrase, verb phrase, etc.). This structure, known as the X-bar schema, is based on the idea that every phrase (XP, X phrase) has a head, which determines the type (syntactic category) of the phrase (X).

The theory was first proposed by Noam Chomsky in 1970 reformulating the ideas of Zellig Harris (1951), and further developed by Ray Jackendoff (1974, 1977a, 1977b), along the lines of the theory of generative grammar put forth in the 1950s by Chomsky. It aimed to simplify and generalize the rules of grammar, addressing limitations of earlier phrase structure models. X-bar theory was an important step forward because it simplified the description of sentence structure. Earlier approaches needed many phrase structure rules, which went against the idea of a simple, underlying system for language. X-bar theory offered a more elegant and economical solution, aligned with the thesis of generative grammar.