deber Imperfect Conjugation
deber — must
The imperfect of deber is regular (debía, debías...) and describes ongoing obligations or debts in the past.
deber Imperfect Forms
When to Use the Imperfect
Use the imperfect to describe background obligations or debts that didn't have a specific end point. It is common when saying what you 'were supposed to' do or money you 'used to owe'.
Notes on deber in the Imperfect
Deber is completely regular in the imperfect. It follows the standard -er ending pattern.
Example Sentences
Yo debía mucho dinero al banco.
I owed a lot of money to the bank.
yo
Debíamos estudiar más para ese examen.
We were supposed to study more for that exam.
nosotros
Ellos debían llegar a las ocho.
They were supposed to arrive at eight.
ellos/ellas/ustedes
Common Mistakes
Mistake: Using the preterite 'debí' for 'I used to owe'.
Correct: Use 'debía'.
Why: The preterite implies a finished debt, while the imperfect describes the state of owing money over time.
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Related Tenses
Present
yo: debo
The present of deber is regular (debo, debes, debe...) and expresses current obligations or debts.
Preterite
yo: debí
The preterite of deber is regular (debí, debiste...) and focuses on a specific moment of obligation or a completed debt.
Future
yo: deberé
The future of deber is regular (deberé, deberás...) and expresses future obligations or probability.
Conditional
yo: debería
The conditional of deber (debería, deberías...) is the go-to way to say 'should' in Spanish.
Present Subjunctive
yo: deba
The present subjunctive of deber (deba, debas...) is used after expressions of doubt, desire, or necessity.
Imperfect Subjunctive
yo: debiera
The imperfect subjunctive of deber (debiera, debieras...) is used in 'if' clauses or for very polite advice.
Affirmative Imperative
yo: debe
The imperative of deber (debe, debed...) is rarely used as it sounds redundant to 'command' an obligation.
Negative Imperative
yo: no debas
The negative imperative (no debas, no debáis...) is used to tell someone not to owe money or things.