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Conjugation Chart

“Deber” (to owe, must) in the Imperfect Tense

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Understanding the Imperfect Tense of “Deber”

The Imperfect Tense of deber is used to express an ongoing obligation, duty or probability in the past. For example, Yo debía estudiar más para el examen. (I should have studied more for the exam.)

Deber is a regular -er verb, so its conjugations in the Imperfect Tense follow the regular pattern for this verb type.

How to Use Deber in the Imperfect Tense

The imperfect tense of deber is used to express an ongoing obligation, duty, or probability in the past.

Obligation or duty in the past: For example, Debía estudiar más para el examen. (I had to study more for the exam.)

Probability in the past: For example, Debía ser muy tarde porque no había nadie en la calle. (It must have been very late because there was nobody on the street.)

Polite request: For example, ¿Debía llamar antes de venir? (Should I have called before coming?)

Habitual action in the past: For example, Cuando era niño, debía ayudar a mi madre con las tareas de la casa. (When I was a child, I had to help my mother with the household chores.)

Conjecture or assumption: For example, Debía estar enfermo porque no vino a trabajar. (He must have been sick because he didn’t come to work.)

Colloquial usage: In some regions, deber in the imperfect tense can be used to express annoyance or frustration, for example, ¡Debías haberme avisado antes! (You should have warned me earlier!)

Real Life Examples of Deber in the Imperfect Tense

Yo debía estudiar más para el examen, pero me distraje con otras cosas. (I should have studied more for the exam, but I got distracted with other things.)

Ellos debían llegar a tiempo a la reunión, pero el tráfico estaba horrible. (They should have arrived on time for the meeting, but the traffic was horrible.)

¿Por qué debías decirle eso a tu hermana? Ahora está muy molesta. (Why did you have to say that to your sister? Now she’s really upset.)

Tú debías haber avisado que ibas a llegar tarde. Estuvimos esperándote por una hora. (You should have let us know you were going to be late. We were waiting for you for an hour.)

Nosotros debíamos haber reservado el hotel con más anticipación para obtener mejores precios. (We should have booked the hotel further in advance to get better rates.)

Ella debía estar en casa estudiando en lugar de salir con sus amigos. (She should have been at home studying instead of going out with her friends.)

Vosotros debíais haber traído algo para compartir a la fiesta. ¡Qué desconsiderados! (You guys should have brought something to share at the party. How inconsiderate!)

Ustedes debían haber pedido instrucciones si no entendían la tarea. (You all should have asked for instructions if you didn’t understand the assignment.)

¿Por qué debías comer tanto? Ahora te sientes mal del estómago. (Why did you have to eat so much? Now your stomach hurts.)

Yo debía haberme ido a la cama más temprano anoche. Estoy muerto de sueño hoy. (I should have gone to bed earlier last night. I’m dead tired today.)

Ellas debían haber practicado más antes del concierto. Su presentación estuvo muy desafinada. (They should have practiced more before the concert. Their performance was really out of tune.)

Tú debías haber escuchado a tus padres cuando te aconsejaron sobre esa decisión. (You should have listened to your parents when they advised you about that decision.)

Nosotros debíamos haber comprado los boletos con más anticipación. ¡Ahora están agotados! (We should have bought the tickets further in advance. Now they’re sold out!)

Vosotros debíais haber llegado más temprano si queríais conseguir buenos asientos. (You guys should have arrived earlier if you wanted to get good seats.)

Él debía haber pedido ayuda en lugar de intentar arreglar el problema él solo. (He should have asked for help instead of trying to fix the problem on his own.)

Conjugation Chart with English Translations

Conjugations of Deber (to owe, must) in the Imperfect Tense (Castilian Spanish) with English Translations:

This post covers Castilian Spanish. For Latin American Spanish, click here

Synonyms

The Imperfect tense is also known as the Past Imperfect, Descriptive Past, Past Progressive, or Imperfect Indicative in English, and as Pretérito Imperfecto, Copretérito, Imperfecto de Indicativo, or Pasado Descriptivo in Spanish.