Complex sentence: Vincent takes her home, they promise each other not to tell Marellus what has happened, she tells Vincent a joke, a pun the punch line for which is "catch up" and he blows her a goodnight kiss.
Split into simpler sentences: Vincent takes her home and they promise each other not to tell Marellus what has happened. As Vincent leaves she tells him a joke, a pun the punch line for which is "catch up" and he blows her a goodnight kiss.