Adjunct (grammar)

In linguistics, an adjunct is an optional, or structurally dispensable, part of a sentence, clause, or phrase that, if removed or discarded, will not otherwise affect the remainder of the sentence. Example: In the sentence John helped Bill in Central Park, the phrase in Central Park is an adjunct.

A more detailed definition of the adjunct emphasizes its attribute as a modifying form, word, or phrase that depends on another form, word, or phrase, being an element of clause structure with adverbial function. An adjunct is not an argument (nor is it a predicative expression), and an argument is not an adjunct. The argument–adjunct distinction is central in most theories of syntax and semantics. The terminology used to denote arguments and adjuncts can vary depending on the theory at hand. Some dependency grammars, for instance, employ the term circonstant (instead of adjunct), following Tesnière (1959).

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

Take the sentence John helped Bill in Central Park on Sunday as an example:

An adverbial adjunct is a sentence element that often establishes the circumstances in which the action or state expressed by the verb takes place. The following sentence uses adjuncts of time and place:

Notice that this example is ambiguous between whether the adjunct in the garden modifies the verb saw (in which case it is Lorna who saw the dog while she was in the garden) or the noun phrase the dog (in which case it is the dog who is in the garden). The definition can be extended to include adjuncts that modify nouns or other parts of speech (see noun adjunct).

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