Final answer:
The adverb in the sentence is 'already,' which indicates the time of Madison's worry. Adverbs can modify verbs, adjectives, and other adverbs and are not always marked by an '-ly' ending.
Step-by-step explanation:
The adverb in the sentence "Madison was already worried about her hectic schedule" is already. An adverb is a word that modifies a verb, an adjective, or another adverb, typically expressing time, manner, place, or degree. In this case, 'already' is modifying the verb 'was worried', indicating the time aspect of Madison's worry - that she was worried by or before the current time. It's important to recognize that while many adverbs do end in '-ly', not all do, and 'already' is one example of this exception.
Understanding the role of adverbs in a sentence can help create more concise and clear writing. For instance, we can compare two sentences: one that is wordy, "There was a really bright light that was shining on the waves in the ocean", and a revised version that cuts out unnecessary words, "A bright light shone on the ocean waves". The second sentence is more direct and easier to comprehend because it uses concrete nouns and action verbs efficiently.