Avverbial

Avverbial, commonly spelled adverbial in English grammar, refers to the function of elements that modify the action or state described by a verb or the entire clause. Adverbials can appear as single words (adverbs), as multiword phrases (adverbial phrases), or as dependent clauses (adverbial clauses). They convey information about time, place, manner, degree, frequency, cause, or attitude toward the assertion.

Adverbs such as quickly, gently, or often are the simplest realizations of an adverbial function. Adverbial phrases, such as in the morning, with great care, or by the river, perform the same function with more detail. Adverbial clauses, such as when the bell rang, because she smiled, or if it rains, provide a fuller subordinate structure that comments on the action.

Adverbials are typically considered adjuncts and can occupy initial, medial, or final positions in the sentence. Their placement can affect emphasis or nuance but rarely changes the core meaning. In many languages, adverbials cooperate with case marking or word order to signal their relation to the verb or predicate.

Note that "adverbial" is a functional label rather than a fixed part of speech. A word or phrase that serves as an adverbial may be an adverb, an adverbial phrase, or an adverbial clause. Some grammars distinguish sentence adverbs (for example, fortunately, apparently) that modify the entire sentence.