the purpose of all verbs is to express what?
I'll try to explain myself with examples:
Sentence without a verb:
- A beautiful slim woman with long blonde hair.
NOTE: There's no action in this sentence, it's only a description of a person.
Sentence with a verb:
- A beautiful slim woman with long blonde hair was walking along the deserted street.
NOTE: Here the verb "walk" explains what does the subject do in the sentence; it isn't only a description, there's also action, something happens.