Adverb clause

An adverbial clause is a dependent clause that functions as an adverb; that is, the entire clause modifies a verb, an adjective, or another adverb. As with all clauses, it contains a subject and predicate, although the subject as well as the (predicate) verb may sometimes be omitted and implied (see below).

An adverbial clause is commonly, but not always, fronted by a subordinate conjunction—sometimes called a trigger word. (In the examples below the adverbial clause is italicized and the subordinate conjunction is bolded.)

According to Sidney Greenbaum and Randolph Quirk, adverbial clauses function mainly as adjuncts or disjuncts, which parts also perform in a sentence as adverbial phrases or as adverbial prepositional phrases (Greenbaum and Quirk,1990). Unlike clauses, phrases do not contain a subject and predicate; they are contrasted here:

Adverbial clauses are divided into several groups according to the actions or senses of their conjunctions:

or the paired (correlative) conjunctions: hardly...when, scarcely...when, barely...when, no sooner...than

Say when something happens by referring to a period or point of time, or to another event.

He came after night had fallen.

We barely had gotten there when mighty Casey struck out.

She is a better cook than I.

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