Adverbs are words that modify
a verb (He drove slowly. — How did he drive?)
an adjective (He drove a very fast car. — How fast was his car?)
another adverb (She moved quite slowly down the aisle. — How slowly did she move?)
As we will see, adverbs often tell when, where, why, or under what conditions something happens or happened. Adverbs frequently end in -ly; however, many words and phrases not ending in -ly serve an adverbial function and an -ly ending is not a guarantee that a word is an adverb. The words lovely, lonely, motherly, friendly, neighborly, for instance, are adjectives:
That lovely woman lives in a friendly neighborhood.
If a group of words containing a subject and verb acts as an adverb (modifying the verb of a sentence), it is called an Adverb Clause:
When this class is over, we're going to the movies.
When a group of words not containing a subject and verb acts as an adverb, it is called an adverbial phrase. Prepositional phrases frequently have adverbial functions (telling place and time, modifying the verb):
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