Les formules au prétérit correspondent à une forme de récit tandis que celles au présent simple correspondent à des indications scéniques type dialogue, théâtre ou script.
Neutre
She was walking down the street when I last saw her.
He approached her
He crossed over to her
He let him in
She followed him down the hall, up the stairs and into his office where she sat down right in front of his desk. she heads out but pauses before leaving she starts out then stops
She turns to him
She turns away from him and heads for the stairway. after a beat he follows her
Ed trails=He tails her
… her two kids in tow

Sans bruit, discrètement, précautionneusement
She tiptoed out of the bedroom not to wake him up.
She sneaked into the room
She snooped around the house
She squeeze back behind the counter and into the back room she minced her way down the path.
He stepped aside to let her go.

Avec dynamisme, agressivité, vitesse, bruit
He jumps up to help her with the door she runs into her house in a total panic she is rushing through each room calling out their names
The kids trooped out of the sitter’s house
Ed’s blustery entrance only added to the sense of chaos.
He stomped back to his office she barrels toward the elevator. Ed trails
She swooped in she is out the door before he could get a chance to finish his sentence to stride along/in/away etc = avancer/entrer/s'éloigner etc à grands pas or à grandes enjambées he was striding up and down the room= il arpentait la pièce in or with a few strides he had caught up with the others = il avait rattrapé les autres en quelques enjambées or foulées
The security guards chased her=les agents de sécurité l’ont poursuivie to storm (one's way) in/out etc :entrer/sortir etc comme un ouragan to breeze in/out etc jauntily = entrer/sortir etc d'un air dégagé to breeze in/out etc briskly entrer/sortir etc = en coup de vent to barrel in/out:away (US) = foncer, aller à toutes