must have been
Eso debe haber sido antes de su 'accidente '.
That must have been before his 'accident'.
A esto debe haber sido a lo que se refería.
This must be what he was referring to.
— Despedidas (2008)
Ella debe haber sido rica en aquellos días.
She must have been rich in those days.
Debe haber sido cosa de su hermana.
It must have been his sister’s doing.
He must have been clever.
La noticia debe haber sido una sorpresa.
The news must have come as a surprise.
— El tiempo contigo (2019)