Here's a breakdown:
* Verbs: Adverbs tell us *how*, *when*, *where*, *why*, or *to what extent* an action is performed.
* Example: The bird sang beautifully. (The adverb "beautifully" modifies the verb "sang".)
* Adjectives: Adverbs can describe the intensity or degree of an adjective.
* Example: The house was extremely large. (The adverb "extremely" modifies the adjective "large".)
* Other adverbs: Adverbs can modify other adverbs to provide further detail.
* Example: He ran very quickly to the store. (The adverb "very" modifies the adverb "quickly".)
Remember: Adverbs are often, but not always, formed by adding "-ly" to an adjective. However, there are many adverbs that don't end in "-ly" (e.g., very, never, always).