Here's why:
* Adverbs modify verbs, adjectives, or other adverbs. "Hurriedly" describes how an action is done (the verb).
* Adverbs often end in "-ly." This is a common ending for adverbs, and "hurriedly" fits that pattern.
Example:
* "She walked hurriedly to the store." ("Hurriedly" modifies the verb "walked" and tells us how she walked.)