had to, was supposed to, should, owed
Debía de tener un problema del corazón porque no se movía.
He must have had a heart problem because he wasn't moving.
— It's Such a Beautiful Day (2012)
Mi hermano debía recogerme en la estación, pero no pude encontrarlo.
My brother was supposed to pick me up at the station, but I couldn't find him.
Por cierto, él debía ir a Leningrado, para festejar con ella el Año Nuevo.
Incidentally, he was supposed to go to Leningrad to celebrate the New Year with her.
— Ирония судьбы, или С легким паром! (1976)
Yo debía de estar en la peluquería.
I must have been at the hairdresser's.
Debía ver que no fuera una trampa Yakuza.
I had to make sure it wasn't a Yakuza trap.
— Tren bala (2022)
Y Pablito debía ir en avión a Leningrado, después del baño.
And Pablito had to go by plane to Leningrad, after his bath.
— Ирония судьбы, или С легким паром! (1976)
It didn't behave as it should have.
I have done for you everything I should have.
— El tigre y el dragón (2000)
No hace mucho, comí algo que no debía.
Not long ago, I ate something I shouldn't have.
— Madre (2009)