The tenses relate to actions over time; now = present. It rains = present and there is no helping verb.
The progressive tense is composed of a helping verb and a verbal ending in "ing."
Rain is occurring; the action is present, but the action is continuous.
Habitual = duration = a repetitive action. This tense is called progressive.
The narrative past is over with. In a fairy tale or legend the story refers to events that happened "once upon a time" and are over with. One slay a dragon only once. "The end" "They lived happily ever after."

Anita W.
08/25/24