Final answer:
The adverb 'closely' in the sentence 'If you read a book closely, you can learn a lot about the author' modifies the verb 'read'.
Step-by-step explanation:
The adverb 'closely' in the sentence 'If you read a book closely, you can learn a lot about the author' modifies the verb 'read.'
An adverb is a part of speech that modifies or describes a verb, adjective, or other adverb. Adverbs often provide information about the manner, frequency, time, place, or degree of an action or state. The adverbs (beautifully, quickly, often, rarely, tomorrow, suddenly, everywhere, onto, extremely, quite) provide additional information about how, when, where, or to what extent the actions or states in the sentences occurred. Adverbs are versatile and play a crucial role in adding detail and nuance to the meaning of a sentence.