When writing fiction, it is important to be as concise as possible and to make every word count. Adjectives and adverbs can be useful at times, but when can wreak havoc with prose when misused.
Let’s recap some grammar. An adjective is a word used to describe a noun, e.g. “the dark forest” or “the young man.” Similarly, an adverb is a word that describes a verb, e.g. “he ran quickly,” or “she screamed loudly.”
There are two cases where adjectives and adverbs can be misused. The first is when the adjective or adverb can be discarded without losing any information. The second case is where the adjective/noun or adverb/verb combination can be replaced with a single noun or verb that conveys the intended meaning more accurately.
Let’s look at the first case. Suppose we have the sentence “The bear roared loudly.” The adverb “loudly” is superfluous (excuse the fancy word!) and can be removed, since “roaring” is by definition “loud.” We don’t need to patronise the reader by reminding them that “roaring” is loud. A similar example that involves an adjective is “The sight of the red blood made him shriek.” Everyone knows that blood is red.
Onto the second case. Suppose we have the sentence “The man ran quickly to the door.” Instead of saying “ran quickly,” we could try “rushed”, “hurried”, “bolted” or “scrambled.” Any one of these single words can replace the adverb+verb combination. “The man scrambled to the door,” reads and sounds better. Another example is “Heavy rain had started.” This can be replaced with “A downpour had started.”
One more example: “The strong wind blew away the woman’s red umbrella.” This can be replaced with “The gust blew away the woman’s umbrella.” Notice the word red was removed, since the fact that the umbrella is red is not relevant in this sentence. If this fact was important to the story, then it would have to be introduced elsewhere, in its own sentence. For example: “The gust blew away the woman’s umbrella. Helen noticed that it was red, reminding her of the blood that she had just seen.”