What is one way that the following sentence can be improved with the addition of an adverb?: The police were pursuing the car as it raced through town.
The police were pursing the car as it raced quickly through town.
Adding the word quickly to the sentence adds more detail. Now we know that the car was racing quickly, not slowly or crazily. Most adverbs end with "ly", so you could pretty much put any adverb in to add more detail.