Here's why:
* Action Verbs: Describe actions that a subject performs. "Sought" implies a deliberate search or attempt to find something.
* Linking Verbs: Connect a subject to a noun, pronoun, or adjective that renames or describes the subject. Common linking verbs include "is," "are," "was," "were," "become," "seem," etc.
Example:
* Action Verb: She sought the answer to the riddle. (She performed the action of searching)
* Linking Verb: The answer is a mystery. (The answer is being described as a mystery)