Deber vs. Deber de... What is the difference?

Question

Deber means to owe

Deber de + inf. is (should,must)?

Can someone explain me the difference?

Can you put an infinitive after deber ?

Answer 1

Deber de makes the most sense to me when translated as "must" int he context of:

"You'd better get home! Your parents must be getting worried!" = "Mas te vale que te vayas a la casa! Los padres deben de estar preocupándose!"

"You worked all day long, you must be exhausted." = "Trabajabas todo el día, debes de estar quemado/agotado."

Deber is usually translated as should, and can be seen a lot in the polite form "Debería/s."

"You should go to bed since you have to get up early." = "Deberías irte a la cama temprano, ya que tienes que madrugar."

There are varying levels of, what's the word..."bossiness" depending on how you conjugate it. If you are at the level where you're trying to distinguish these types of subtle differences, I would recommend "Breaking out of Beginner's Spanish." It is fabulous for these types of things and really cheap on Amazon.

Chao!

Answer 2

When deber or deber de is followed by an infinitive, it acts as an auxiliary verb to the verb in the infinitive (i.e. it combines to form a perífrasis verbal)

The following is excerpted from the DPD

deber + infinitivo.

Denota obligación:

«Debo cumplir con mi misión» ? I must (have to) complete my mission. [obligation]

Diccionario panhispánico de dudas ©2005
Real Academia Española © Todos los derechos reservados

deber de + infinitivo.

Denota probabilidad o suposición:

«No se oye nada de ruido en la casa. Los viejos deben de haber salido» ? There wasn't a sound in the house. The old folks must have left. [supposition]

No obstante, con este sentido, la lengua culta admite también el uso sin preposición: (Nonetheless, with the idea of probability or supposition, it is not uncommon to see deber without the preposition de)

«Marianita, su hija, debe tener unos veinte años» ? Marianita, her daughter, ought to/must be 20 years old. [supposition]

Diccionario panhispánico de dudas ©2005
Real Academia Española © Todos los derechos reservados

I think you forgot "duty" - Cabeza_215, Jan 31, 2011

@Cabeza: I think that you have already explained adequately the use of "deber" as a noun (i.e. to mean duty). I was just pointing out the differences in usage as a "perífrasis verbal." - Izanoni1, Jan 31, 2011

Ok thanks :) - Cabeza_215, Jan 31, 2011

Nice explaination, Ira. Even though people sometimes omit "de" with supposition, it´s more proper to use it - 005faa61, Jan 31, 2011

very useful - dewclaw, Feb 1, 2011

Answer 3

And sometimes people uses incorrectly

deber + de

with the idea of obligation:

Debes de hacer la tarea. (incorrect)

The correct form would be

Debes hacer la tarea. (correct)

Answer 4

"Deber" means owe. For example: Me debes plata = You owe me money. Also "Deber" means duty when (it is) used as a noun and must when (it is) used as a verb. For example: Debes hacer tu tarea = You must do your homework. Or The duty to answer this question = El deber de responder esta pregunta.

I hope it helps.

Nice explanation :)......just a suggestion: "duty for noun and must for verb" → "duty when (it is) used as a noun and must when (it is) used as a verb" - Izanoni1, Jan 31, 2011

Thanks ! - Cabeza_215, Jan 31, 2011

Don't you mean "El deber de responder a esta pregunta" - samdie, Jan 31, 2011