Verbs that show actions or 'action verbs' are the most used verbs.
Action verbs take 's' in the third person when they are singular verbs:
He lives in Athens.
She works in the city.
It rains a lot in February.
Negative sentences need 'do not', 'does not', or 'did not'.
He does not live in Athens.
She does not work in the city.
It does not rain in August.
It did not rain in June.