Adverb clauses are groups of words that function as an adverb. To understand this, you need to know about clauses and the functions of adverbs.
A clause is a group of words that contains a subject and verb (predicate). This differs from a phrase, which does not have a subject and a verb, like “to the park.” Clauses can be independent or dependent. Independent clauses are called sentences as they can stand alone and express a complete thought.
Dependent clauses, or subordinate clauses, are subordinate to something else, usually an independent clause, and depend on it for meaning. Here are some examples with the dependent clause underlined:
You can see that each underlined clause cannot stand on its own, but needs a clause to help it make sense or to help it complete a thought.
Adverb clauses are clauses that function as adverbs. Since they are dependent clauses, they must have a subordinating conjunction to connect them to the other clause. Subordinating conjunctions can be arranged according to the purpose of the clause they begin. Here are some examples of subordinating conjunctions:
Most of the time, an adverb clause will be separated from the other clause with a comma. Here are a few examples of sentences with and without commas:
Since adverb clauses function as adverbs, let’s look at the functions of adverbs. Adverbs modify verbs, adjectives, and other adverbs. They tell why, when, where, how, how much, and how often an action occurs. They can begin a sentence that is a question, and give more information. Here are some examples according to what the adverb is modifying:
Adverb clauses can modify by telling the place, time, cause, and purpose of an action. They can also show concession and condition. Basically they answer the questions: Where?, when?, why?, and under what conditions? Here are some examples with the adverb clause underlined: