There is more than one way to say your character is feeling happy, sad, angry, or scared. Using the same words repeatedly to describe how your characters feels in different situations can affect how readers interpret your characters and their personalities. Your character might come across as being flat or limited in their feelings and responses.
Feelings and emotions aren’t straightforward. There are degrees and levels.
Let’s look at angry. What makes you angry? Something making you late to work? Someone lying to you? Ruining your favorite shirt? Your dog peeing in the house? Someone eating the last chocolate chip cookie? Being told you have to work the weekend? Finding out your significant other cheated or kept a secret from you?
Yes, each of these things could make someone angry. But do you feel the same degree or level of anger with each event? Is the anger felt so encompassing that you can’t think of anything else right now or will the anger dissipate in a matter of moments?
If a character is angry in all these situations, the feeling conveyed to a reader by the word angry will lose its effect. If a character is angry when the dog peed in the house or they were late to work, when they are angry later because their significant other cheated on them (which might be a pivotal plot point), you’ve lost the feeling behind the word.
To readers, the new event isn’t a big deal for your character because your character felt the same way when they were cheated on as they did when the dog peed in the house or they were late to work. Using synonyms for words that express feelings and emotions can help readers understand more about who your character is through their emotional responses.
Using synonyms for emotions and feelings will allow you to further develop your character and show what is more important to them. A character might be upset the dog peed in the house (a minor issue) and frustrated when they were late to work (more important). When their significant other cheats on them, a character might be irate or furious (major issue).