Imperfecto de subjuntivo para el sujeto ellos/ellas/ustedes del verbo caber.

caber

En su momento los inquilinos potenciales eran reluctantes a alquilar las habitaciones porque las paredes tenían formas irregulares y estaban preocupados de que los muebles no cupiesen.
At the time potential tenants were reluctant to hire the rooms because the walls were irregularly shaped and they were concerned that their furniture would not fit.
Palabra del día
la leña