Here's why:
* Common nouns are general names for people, places, things, or ideas (e.g., dog, city, table, happiness).
* Verbs describe actions or states of being.
"Fought" tells us about an action that happened in the past.
Here's an example:
* The soldiers fought bravely. (Fought is the past tense of the verb "fight")
To use a common noun related to "fought," you could say:
* The soldiers had a battle. (Battle is a common noun referring to a fight)