The modal operators □ and ◊ stand for alethic necessity and possibility.

She sat completely alone at the very back of the sea-themed restaurant, amid papier-mâché starfish and plastic shrimp.

the Jugulary Vein of a little Dog

The huge square box, parquet-floored and high-ceilinged, had been arranged to display a suite of bedroom furniture designed and made in the halcyon days of the last quarter of the nineteenth century,[…].